21925715 has 16 divisors (see below), whose sum is σ = 31653120. Its totient is φ = 14243040.

The previous prime is 21925697. The next prime is 21925741. The reversal of 21925715 is 51752912.

It is a happy number.

It is not a de Polignac number, because 21925715 - 2¹⁴ = 21909331 is a prime.

It is a super-2 number, since 2×21925715² = 961473956522450, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15821 + ... + 17150.

It is an arithmetic number, because the mean of its divisors is an integer number (1978320).

Almost surely, 2^21925715 is an apocalyptic number.

21925715 is a deficient number, since it is larger than the sum of its proper divisors (9727405).

21925715 is a wasteful number, since it uses less digits than its factorization.

21925715 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 33002.

The product of its digits is 6300, while the sum is 32.

The square root of 21925715 is about 4682.4902562632. The cubic root of 21925715 is about 279.8881994129. Note that the first 3 decimals are identical.

The spelling of 21925715 in words is "twenty-one million, nine hundred twenty-five thousand, seven hundred fifteen".