21837164 has 12 divisors (see below), whose sum is σ = 38248224. Its totient is φ = 10909104.

The previous prime is 21837161. The next prime is 21837181. The reversal of 21837164 is 46173812.

It is a self number, because there is not a number n which added to its sum of digits gives 21837164.

It is not an unprimeable number, because it can be changed into a prime (21837161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6509 + ... + 9275.

It is an arithmetic number, because the mean of its divisors is an integer number (3187352).

Almost surely, 2^21837164 is an apocalyptic number.

It is an amenable number.

21837164 is a deficient number, since it is larger than the sum of its proper divisors (16411060).

21837164 is a wasteful number, since it uses less digits than its factorization.

21837164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4744 (or 4742 counting only the distinct ones).

The product of its digits is 8064, while the sum is 32.

The square root of 21837164 is about 4673.0251443792. The cubic root of 21837164 is about 279.5108978377.

The spelling of 21837164 in words is "twenty-one million, eight hundred thirty-seven thousand, one hundred sixty-four".