21620542672320 has 56 divisors (see below), whose sum is σ = 68645222987664. Its totient is φ = 5765478045696.

The previous prime is 21620542672301. The next prime is 21620542672343. The reversal of 21620542672320 is 2327624502612.

It is a happy number.

It is a super-2 number, since 2×21620542672320² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11260698349 + ... + 11260700268.

Almost surely, 2^{21620542672320} is an apocalyptic number.

21620542672320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21620542672320 is an abundant number, since it is smaller than the sum of its proper divisors (47024680315344).

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

21620542672320 is a wasteful number, since it uses less digits than its factorization.

21620542672320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22521398637 (or 22521398627 counting only the distinct ones).

The product of its (nonzero) digits is 483840, while the sum is 42.

The spelling of 21620542672320 in words is "twenty-one trillion, six hundred twenty billion, five hundred forty-two million, six hundred seventy-two thousand, three hundred twenty".