21925605 has 32 divisors (see below), whose sum is σ = 38021760. Its totient is φ = 10725120.

The previous prime is 21925591. The next prime is 21925613. The reversal of 21925605 is 50652912.

It is a happy number.

It is not a de Polignac number, because 21925605 - 2⁵ = 21925573 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 44410 + ... + 44900.

It is an arithmetic number, because the mean of its divisors is an integer number (1188180).

Almost surely, 2^21925605 is an apocalyptic number.

It is an amenable number.

21925605 is a deficient number, since it is larger than the sum of its proper divisors (16096155).

21925605 is a wasteful number, since it uses less digits than its factorization.

21925605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 741.

The product of its (nonzero) digits is 5400, while the sum is 30.

The square root of 21925605 is about 4682.4785103618. The cubic root of 21925605 is about 279.8877313514.

The spelling of 21925605 in words is "twenty-one million, nine hundred twenty-five thousand, six hundred five".