21626725 has 6 divisors (see below), whose sum is σ = 26817170. Its totient is φ = 17301360.

The previous prime is 21626719. The next prime is 21626743. The reversal of 21626725 is 52762612.

It can be written as a sum of positive squares in 3 ways, for example, as 7496644 + 14130081 = 2738^2 + 3759^2 .

It is not a de Polignac number, because 21626725 - 2¹¹ = 21624677 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 432510 + ... + 432559.

Almost surely, 2^21626725 is an apocalyptic number.

21626725 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21626725 is a deficient number, since it is larger than the sum of its proper divisors (5190445).

21626725 is an equidigital number, since it uses as much as digits as its factorization.

21626725 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 865079 (or 865074 counting only the distinct ones).

The product of its digits is 10080, while the sum is 31.

The square root of 21626725 is about 4650.4542788850. The cubic root of 21626725 is about 278.6101405141.

The spelling of 21626725 in words is "twenty-one million, six hundred twenty-six thousand, seven hundred twenty-five".