21938706 has 24 divisors (see below), whose sum is σ = 48820044. Its totient is φ = 7115040.

The previous prime is 21938699. The next prime is 21938713. The reversal of 21938706 is 60783912.

It is an interprime number because it is at equal distance from previous prime (21938699) and next prime (21938713).

It can be written as a sum of positive squares in 2 ways, for example, as 17715681 + 4223025 = 4209^2 + 2055^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 15805 + ... + 17136.

Almost surely, 2^21938706 is an apocalyptic number.

21938706 is an abundant number, since it is smaller than the sum of its proper divisors (26881338).

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

21938706 is a wasteful number, since it uses less digits than its factorization.

21938706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32986 (or 32983 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 21938706 is about 4683.8772400651. The cubic root of 21938706 is about 279.9434664775.

The spelling of 21938706 in words is "twenty-one million, nine hundred thirty-eight thousand, seven hundred six".