21186081874944 has 264 divisors, whose sum is σ = 72986672251680. Its totient is φ = 6053165862912.

The previous prime is 21186081874933. The next prime is 21186081875011. The reversal of 21186081874944 is 44947818068112.

21186081874944 is a `hidden beast` number, since 2 + 1 + 1 + 8 + 60 + 8 + 1 + 87 + 494 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 6464422 + ... + 9173925.

It is an arithmetic number, because the mean of its divisors is an integer number (276464667620).

Almost surely, 2^{21186081874944} is an apocalyptic number.

21186081874944 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21186081874944 is an abundant number, since it is smaller than the sum of its proper divisors (51800590376736).

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

21186081874944 is a wasteful number, since it uses less digits than its factorization.

21186081874944 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15638390 (or 15638359 counting only the distinct ones).

The product of its (nonzero) digits is 24772608, while the sum is 63.

The spelling of 21186081874944 in words is "twenty-one trillion, one hundred eighty-six billion, eighty-one million, eight hundred seventy-four thousand, nine hundred forty-four".