21580264857888 has 72 divisors (see below), whose sum is σ = 66947867125776. Its totient is φ = 6539474198400.

The previous prime is 21580264857871. The next prime is 21580264857913. The reversal of 21580264857888 is 88875846208512.

21580264857888 is a `hidden beast` number, since 2 + 1 + 5 + 8 + 0 + 2 + 6 + 48 + 578 + 8 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (72).

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, 3405972978 + ... + 3405979313.

It is an arithmetic number, because the mean of its divisors is an integer number (929831487858).

Almost surely, 2^{21580264857888} is an apocalyptic number.

It is an amenable number.

21580264857888 is an abundant number, since it is smaller than the sum of its proper divisors (45367602267888).

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

21580264857888 is a wasteful number, since it uses less digits than its factorization.

21580264857888 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6811952318 (or 6811952307 counting only the distinct ones).

The product of its (nonzero) digits is 550502400, while the sum is 72.

The spelling of 21580264857888 in words is "twenty-one trillion, five hundred eighty billion, two hundred sixty-four million, eight hundred fifty-seven thousand, eight hundred eighty-eight".