Search a number
BaseRepresentation
bin100111111000…
…1010001111110
31110100101211000
41033301101332
520323124410
62024111130
7342512454
oct117612176
943311730
1020911230
1110892a0a
1270054a6
134442112
142ac49d4
151c80dc0
hex13f147e

20911230 has 64 divisors (see below), whose sum is σ = 57153600. Its totient is φ = 5437440.

The previous prime is 20911223. The next prime is 20911243. The reversal of 20911230 is 3211902.

It is a happy number.

It is a super-2 number, since 2×209112302 = 874559080225800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10126 + ... + 12014.

It is an arithmetic number, because the mean of its divisors is an integer number (893025).

Almost surely, 220911230 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20911230, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28576800).

20911230 is an abundant number, since it is smaller than the sum of its proper divisors (36242370).

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

20911230 is a wasteful number, since it uses less digits than its factorization.

20911230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1946 (or 1940 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 20911230 is about 4572.8798366019. The cubic root of 20911230 is about 275.5031230329.

It can be divided in two parts, 2091 and 1230, that added together give a triangular number (3321 = T81).

The spelling of 20911230 in words is "twenty million, nine hundred eleven thousand, two hundred thirty".