21164502252 has 24 divisors (see below), whose sum is σ = 50588323632. Its totient is φ = 6882764800.

The previous prime is 21164502221. The next prime is 21164502259. The reversal of 21164502252 is 25220546112.

It is not an unprimeable number, because it can be changed into a prime (21164502259) 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 7 ways as a sum of consecutive naturals, for example, 21508149 + ... + 21509132.

It is an arithmetic number, because the mean of its divisors is an integer number (2107846818).

Almost surely, 2^21164502252 is an apocalyptic number.

It is an amenable number.

21164502252 is an abundant number, since it is smaller than the sum of its proper divisors (29423821380).

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

21164502252 is a wasteful number, since it uses less digits than its factorization.

21164502252 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43017329 (or 43017327 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 30.

The spelling of 21164502252 in words is "twenty-one billion, one hundred sixty-four million, five hundred two thousand, two hundred fifty-two".