21725944 has 16 divisors (see below), whose sum is σ = 40988520. Its totient is φ = 10795680.

The previous prime is 21725933. The next prime is 21725953. The reversal of 21725944 is 44952712.

It is a super-2 number, since 2×21725944² = 944033285382272, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7027 + ... + 9634.

Almost surely, 2^21725944 is an apocalyptic number.

It is an amenable number.

21725944 is a deficient number, since it is larger than the sum of its proper divisors (19262576).

21725944 is a wasteful number, since it uses less digits than its factorization.

21725944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16830 (or 16826 counting only the distinct ones).

The product of its digits is 20160, while the sum is 34.

The square root of 21725944 is about 4661.1097391072. The cubic root of 21725944 is about 279.0355594164.

The spelling of 21725944 in words is "twenty-one million, seven hundred twenty-five thousand, nine hundred forty-four".