21626425 has 6 divisors (see below), whose sum is σ = 26816798. Its totient is φ = 17301120.

The previous prime is 21626419. The next prime is 21626443. The reversal of 21626425 is 52462612.

It can be written as a sum of positive squares in 3 ways, for example, as 2019241 + 19607184 = 1421^2 + 4428^2 .

It is not a de Polignac number, because 21626425 - 2⁹ = 21625913 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21626393 and 21626402.

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, 432504 + ... + 432553.

Almost surely, 2^21626425 is an apocalyptic number.

21626425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

21626425 is a deficient number, since it is larger than the sum of its proper divisors (5190373).

21626425 is an equidigital number, since it uses as much as digits as its factorization.

21626425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 865067 (or 865062 counting only the distinct ones).

The product of its digits is 5760, while the sum is 28.

The square root of 21626425 is about 4650.4220238598. The cubic root of 21626425 is about 278.6088522403.

The spelling of 21626425 in words is "twenty-one million, six hundred twenty-six thousand, four hundred twenty-five".