21625531392 has 88 divisors (see below), whose sum is σ = 58150946736. Its totient is φ = 7144603648.

The previous prime is 21625531357. The next prime is 21625531399. The reversal of 21625531392 is 29313552612.

It is a self number, because there is not a number n which added to its sum of digits gives 21625531392.

It is not an unprimeable number, because it can be changed into a prime (21625531399) 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, 315988 + ... + 378284.

Almost surely, 2^21625531392 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21625531392, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29075473368).

21625531392 is an abundant number, since it is smaller than the sum of its proper divisors (36525415344).

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

21625531392 is a wasteful number, since it uses less digits than its factorization.

21625531392 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 62433 (or 62415 counting only the distinct ones).

The product of its digits is 97200, while the sum is 39.

The spelling of 21625531392 in words is "twenty-one billion, six hundred twenty-five million, five hundred thirty-one thousand, three hundred ninety-two".