21611831232 has 56 divisors (see below), whose sum is σ = 57545595856. Its totient is φ = 7158048768.

The previous prime is 21611831209. The next prime is 21611831237. The reversal of 21611831232 is 23213811612.

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 21611831232.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21611831237) 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, 328333 + ... + 388620.

It is an arithmetic number, because the mean of its divisors is an integer number (1027599926).

Almost surely, 2^21611831232 is an apocalyptic number.

It is an amenable number.

21611831232 is an abundant number, since it is smaller than the sum of its proper divisors (35933764624).

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

21611831232 is a wasteful number, since it uses less digits than its factorization.

21611831232 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 717125 (or 717115 counting only the distinct ones).

The product of its digits is 3456, while the sum is 30.

The spelling of 21611831232 in words is "twenty-one billion, six hundred eleven million, eight hundred thirty-one thousand, two hundred thirty-two".