21208255902504 has 80 divisors (see below), whose sum is σ = 64803004168320. Its totient is φ = 6426744210720.

The previous prime is 21208255902403. The next prime is 21208255902539. The reversal of 21208255902504 is 40520955280212.

21208255902504 is a `hidden beast` number, since 2 + 1 + 2 + 0 + 8 + 2 + 5 + 590 + 2 + 50 + 4 = 666.

It is a super-4 number, since 4×21208255902504⁴ (a number of 54 digits) contains 4444 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21208255902504.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1487665144 + ... + 1487679399.

It is an arithmetic number, because the mean of its divisors is an integer number (810037552104).

Almost surely, 2^{21208255902504} is an apocalyptic number.

21208255902504 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21208255902504 is an abundant number, since it is smaller than the sum of its proper divisors (43594748265816).

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

21208255902504 is a wasteful number, since it uses less digits than its factorization.

21208255902504 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2975344572 (or 2975344559 counting only the distinct ones).

The product of its (nonzero) digits is 576000, while the sum is 45.

The spelling of 21208255902504 in words is "twenty-one trillion, two hundred eight billion, two hundred fifty-five million, nine hundred two thousand, five hundred four".