21710625 has 20 divisors (see below), whose sum is σ = 36175920. Its totient is φ = 11578000.

The previous prime is 21710617. The next prime is 21710639. The reversal of 21710625 is 52601712.

It is not a de Polignac number, because 21710625 - 2³ = 21710617 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21710595 and 21710604.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 3915 + ... + 7664.

It is an arithmetic number, because the mean of its divisors is an integer number (1808796).

Almost surely, 2^21710625 is an apocalyptic number.

21710625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21710625 is a deficient number, since it is larger than the sum of its proper divisors (14465295).

21710625 is an equidigital number, since it uses as much as digits as its factorization.

21710625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11602 (or 11587 counting only the distinct ones).

The product of its (nonzero) digits is 840, while the sum is 24.

The square root of 21710625 is about 4659.4661711402. The cubic root of 21710625 is about 278.9699611806.

The spelling of 21710625 in words is "twenty-one million, seven hundred ten thousand, six hundred twenty-five".