21131210984 has 16 divisors (see below), whose sum is σ = 42668791620. Its totient is φ = 9752866560.

The previous prime is 21131210983. The next prime is 21131211047. The reversal of 21131210984 is 48901213112.

It can be written as a sum of positive squares in 2 ways, for example, as 20652564100 + 478646884 = 143710^2 + 21878^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21131210984.

It is not an unprimeable number, because it can be changed into a prime (21131210983) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 101592257 + ... + 101592464.

Almost surely, 2^21131210984 is an apocalyptic number.

It is an amenable number.

21131210984 is an abundant number, since it is smaller than the sum of its proper divisors (21537580636).

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

21131210984 is a wasteful number, since it uses less digits than its factorization.

21131210984 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 203184740 (or 203184736 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 32.

The spelling of 21131210984 in words is "twenty-one billion, one hundred thirty-one million, two hundred ten thousand, nine hundred eighty-four".