21008416885992 has 80 divisors (see below), whose sum is σ = 59953265267940. Its totient is φ = 6870677209344.

The previous prime is 21008416885903. The next prime is 21008416886027. The reversal of 21008416885992 is 29958861480012.

21008416885992 is a `hidden beast` number, since 2 + 1 + 0 + 0 + 8 + 416 + 88 + 59 + 92 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 16543791568836 + 4464625317156 = 4067406^2 + 2112966^2 .

It is a Smith number, since the sum of its digits (63) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 305818453 + ... + 305887140.

Almost surely, 2^{21008416885992} is an apocalyptic number.

It is an amenable number.

21008416885992 is an abundant number, since it is smaller than the sum of its proper divisors (38944848381948).

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

21008416885992 is a wasteful number, since it uses less digits than its factorization.

21008416885992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 611705664 (or 611705651 counting only the distinct ones).

The product of its (nonzero) digits is 19906560, while the sum is 63.

The spelling of 21008416885992 in words is "twenty-one trillion, eight billion, four hundred sixteen million, eight hundred eighty-five thousand, nine hundred ninety-two".