21656052144 has 60 divisors (see below), whose sum is σ = 60623331912. Its totient is φ = 7216723200.

The previous prime is 21656052091. The next prime is 21656052163. The reversal of 21656052144 is 44125065612.

21656052144 is a `hidden beast` number, since 2 + 1 + 6 + 5 + 605 + 2 + 1 + 44 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 21656052099 and 21656052108.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 570724 + ... + 607484.

Almost surely, 2^21656052144 is an apocalyptic number.

21656052144 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21656052144 is an abundant number, since it is smaller than the sum of its proper divisors (38967279768).

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

21656052144 is a wasteful number, since it uses less digits than its factorization.

21656052144 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40866 (or 40857 counting only the distinct ones).

The product of its (nonzero) digits is 57600, while the sum is 36.

The spelling of 21656052144 in words is "twenty-one billion, six hundred fifty-six million, fifty-two thousand, one hundred forty-four".