20624425 has 6 divisors (see below), whose sum is σ = 25574318. Its totient is φ = 16499520.

The previous prime is 20624381. The next prime is 20624447. The reversal of 20624425 is 52442602.

It can be written as a sum of positive squares in 3 ways, for example, as 21904 + 20602521 = 148^2 + 4539^2 .

It is not a de Polignac number, because 20624425 - 2¹⁷ = 20493353 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25), and also a Moran number because the ratio is a prime number: 824977 = 20624425 / (2 + 0 + 6 + 2 + 4 + 4 + 2 + 5).

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20624425.

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, 412464 + ... + 412513.

Almost surely, 2^20624425 is an apocalyptic number.

20624425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

20624425 is a deficient number, since it is larger than the sum of its proper divisors (4949893).

20624425 is an equidigital number, since it uses as much as digits as its factorization.

20624425 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 824987 (or 824982 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 25.

The square root of 20624425 is about 4541.4122252885. The cubic root of 20624425 is about 274.2377791020.

The spelling of 20624425 in words is "twenty million, six hundred twenty-four thousand, four hundred twenty-five".