21695525 has 12 divisors (see below), whose sum is σ = 27028032. Its totient is φ = 17275440.

The previous prime is 21695503. The next prime is 21695551. The reversal of 21695525 is 52559612.

It is not a de Polignac number, because 21695525 - 2⁸ = 21695269 is a prime.

It is a Duffinian number.

It is a congruent number.

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, 3764 + ... + 7586.

It is an arithmetic number, because the mean of its divisors is an integer number (2252336).

Almost surely, 2^21695525 is an apocalyptic number.

21695525 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21695525 is a deficient number, since it is larger than the sum of its proper divisors (5332507).

21695525 is a wasteful number, since it uses less digits than its factorization.

21695525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4060 (or 4055 counting only the distinct ones).

The product of its digits is 27000, while the sum is 35.

The square root of 21695525 is about 4657.8455320030. The cubic root of 21695525 is about 278.9052705296.

The spelling of 21695525 in words is "twenty-one million, six hundred ninety-five thousand, five hundred twenty-five".