Search a number
-
+
31111111120 = 2451722875817
BaseRepresentation
bin11100111110010111…
…011110000111010000
32222022012001012021211
4130332113132013100
51002203421023440
622143043025504
72150651036605
oct347627360720
988265035254
1031111111120
1112215458291
12604306b294
132c1a6362bb
141711c3a6ac
15c21456eea
hex73e5de1d0

31111111120 has 40 divisors (see below), whose sum is σ = 76588238664. Its totient is φ = 11712417792.

The previous prime is 31111111111. The next prime is 31111111121. The reversal of 31111111120 is 2111111113.

It can be written as a sum of positive squares in 4 ways, for example, as 1875582864 + 29235528256 = 43308^2 + 170984^2 .

It is a tau number, because it is divible by the number of its divisors (40).

It is a self number, because there is not a number n which added to its sum of digits gives 31111111120.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31111111121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11436549 + ... + 11439268.

Almost surely, 231111111120 is an apocalyptic number.

It is an amenable number.

31111111120 is an abundant number, since it is smaller than the sum of its proper divisors (45477127544).

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

31111111120 is a wasteful number, since it uses less digits than its factorization.

31111111120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22875847 (or 22875841 counting only the distinct ones).

The product of its (nonzero) digits is 6, while the sum is 13.

Adding to 31111111120 its reverse (2111111113), we get a palindrome (33222222233).

The spelling of 31111111120 in words is "thirty-one billion, one hundred eleven million, one hundred eleven thousand, one hundred twenty".

Divisors: 1 2 4 5 8 10 16 17 20 34 40 68 80 85 136 170 272 340 680 1360 22875817 45751634 91503268 114379085 183006536 228758170 366013072 388888889 457516340 777777778 915032680 1555555556 1830065360 1944444445 3111111112 3888888890 6222222224 7777777780 15555555560 31111111120