21372576056 has 128 divisors (see below), whose sum is σ = 46825128000. Its totient is φ = 9061797888.

The previous prime is 21372576041. The next prime is 21372576157. The reversal of 21372576056 is 65067527312.

It is a junction number, because it is equal to n+sod(n) for n = 21372575998 and 21372576016.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 9319646 + ... + 9321938.

Almost surely, 2^21372576056 is an apocalyptic number.

21372576056 is a gapful number since it is divisible by the number (26) 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 21372576056, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23412564000).

21372576056 is an abundant number, since it is smaller than the sum of its proper divisors (25452551944).

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

21372576056 is a wasteful number, since it uses less digits than its factorization.

21372576056 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2473 (or 2469 counting only the distinct ones).

The product of its (nonzero) digits is 529200, while the sum is 44.

The spelling of 21372576056 in words is "twenty-one billion, three hundred seventy-two million, five hundred seventy-six thousand, fifty-six".