21391742882988 has 42 divisors (see below), whose sum is σ = 56127649115244. Its totient is φ = 7130580960024.

The previous prime is 21391742882987. The next prime is 21391742883079. The reversal of 21391742882988 is 88928824719312.

21391742882988 is a `hidden beast` number, since 2 + 1 + 39 + 1 + 7 + 428 + 82 + 98 + 8 = 666.

It is not an unprimeable number, because it can be changed into a prime (21391742882987) by changing a digit.

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 13 ways as a sum of consecutive naturals, for example, 3667991406 + ... + 3667997237.

It is an arithmetic number, because the mean of its divisors is an integer number (1336372597982).

Almost surely, 2^{21391742882988} is an apocalyptic number.

It is an amenable number.

21391742882988 is an abundant number, since it is smaller than the sum of its proper divisors (34735906232256).

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

21391742882988 is an equidigital number, since it uses as much as digits as its factorization.

21391742882988 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7335988665 (or 7335988648 counting only the distinct ones).

The product of its digits is 222953472, while the sum is 72.

The spelling of 21391742882988 in words is "twenty-one trillion, three hundred ninety-one billion, seven hundred forty-two million, eight hundred eighty-two thousand, nine hundred eighty-eight".