21938504 has 32 divisors (see below), whose sum is σ = 49057920. Its totient is φ = 8992896.

The previous prime is 21938491. The next prime is 21938533. The reversal of 21938504 is 40583912.

It is a Smith number, since the sum of its digits (32) coincides with the sum of the digits of its prime factors.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 7229 + ... + 9804.

It is an arithmetic number, because the mean of its divisors is an integer number (1533060).

Almost surely, 2^21938504 is an apocalyptic number.

It is an amenable number.

21938504 is an abundant number, since it is smaller than the sum of its proper divisors (27119416).

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

21938504 is a wasteful number, since it uses less digits than its factorization.

21938504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17069 (or 17065 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 32.

The square root of 21938504 is about 4683.8556766835. The cubic root of 21938504 is about 279.9426072844.

The spelling of 21938504 in words is "twenty-one million, nine hundred thirty-eight thousand, five hundred four".