Search a number
-
+
21111000 = 2335331227
BaseRepresentation
bin101000010001…
…0000011011000
31110201112211220
41100202003120
520401023000
62032252040
7344304051
oct120420330
943645756
1021111000
1110a0a009
1270a1020
1344b2021
142b37728
151cc01a0
hex14220d8

21111000 has 128 divisors (see below), whose sum is σ = 68290560. Its totient is φ = 5424000.

The previous prime is 21110989. The next prime is 21111007. The reversal of 21111000 is 11112.

It is a Harshad number since it is a multiple of its sum of digits (6).

It is a super Niven number, because it is divisible the sum of any subset of its (nonzero) digits.

It is a nialpdrome in base 10.

It is a self number, because there is not a number n which added to its sum of digits gives 21111000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21111007) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 92887 + ... + 93113.

It is an arithmetic number, because the mean of its divisors is an integer number (533520).

Almost surely, 221111000 is an apocalyptic number.

21111000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21111000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34145280).

21111000 is an abundant number, since it is smaller than the sum of its proper divisors (47179560).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21111000 is a wasteful number, since it uses less digits than its factorization.

21111000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282 (or 268 counting only the distinct ones).

The product of its (nonzero) digits is 2, while the sum is 6.

The square root of 21111000 is about 4594.6708260767. The cubic root of 21111000 is about 276.3776598535.

Adding to 21111000 its reverse (11112), we get a palindrome (21122112).

It can be divided in two parts, 211 and 11000, that added together give a palindrome (11211).

The spelling of 21111000 in words is "twenty-one million, one hundred eleven thousand".

Divisors: 1 2 3 4 5 6 8 10 12 15 20 24 25 30 31 40 50 60 62 75 93 100 120 124 125 150 155 186 200 227 248 250 300 310 372 375 454 465 500 600 620 681 744 750 775 908 930 1000 1135 1240 1362 1500 1550 1816 1860 2270 2325 2724 3000 3100 3405 3720 3875 4540 4650 5448 5675 6200 6810 7037 7750 9080 9300 11350 11625 13620 14074 15500 17025 18600 21111 22700 23250 27240 28148 28375 31000 34050 35185 42222 45400 46500 56296 56750 68100 70370 84444 85125 93000 105555 113500 136200 140740 168888 170250 175925 211110 227000 281480 340500 351850 422220 527775 681000 703700 844440 879625 1055550 1407400 1759250 2111100 2638875 3518500 4222200 5277750 7037000 10555500 21111000