21164542377984 has 90 divisors (see below), whose sum is σ = 61140145834040. Its totient is φ = 7054847410176.

The previous prime is 21164542377971. The next prime is 21164542377989. The reversal of 21164542377984 is 48977324546112.

21164542377984 is a `hidden beast` number, since 2 + 1 + 1 + 6 + 4 + 542 + 3 + 7 + 7 + 9 + 84 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21164542377989) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 71618164 + ... + 71913075.

Almost surely, 2^{21164542377984} is an apocalyptic number.

21164542377984 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

21164542377984 is an abundant number, since it is smaller than the sum of its proper divisors (39975603456056).

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

21164542377984 is an equidigital number, since it uses as much as digits as its factorization.

21164542377984 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143531273 (or 143531244 counting only the distinct ones).

The product of its digits is 81285120, while the sum is 63.

The spelling of 21164542377984 in words is "twenty-one trillion, one hundred sixty-four billion, five hundred forty-two million, three hundred seventy-seven thousand, nine hundred eighty-four".