21678476803572 has 12 divisors (see below), whose sum is σ = 50583112541696. Its totient is φ = 7226158934520.

The previous prime is 21678476803567. The next prime is 21678476803751. The reversal of 21678476803572 is 27530867487612.

It is a tau number, because it is divible by the number of its divisors (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 903269866804 + ... + 903269866827.

Almost surely, 2^{21678476803572} is an apocalyptic number.

It is an amenable number.

21678476803572 is an abundant number, since it is smaller than the sum of its proper divisors (28904635738124).

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

21678476803572 is a wasteful number, since it uses less digits than its factorization.

21678476803572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1806539733638 (or 1806539733636 counting only the distinct ones).

The product of its (nonzero) digits is 189665280, while the sum is 66.

The spelling of 21678476803572 in words is "twenty-one trillion, six hundred seventy-eight billion, four hundred seventy-six million, eight hundred three thousand, five hundred seventy-two".