646625025 has 30 divisors (see below), whose sum is σ = 1197776822. Its totient is φ = 344865600.

The previous prime is 646625017. The next prime is 646625027. The reversal of 646625025 is 520526646.

646625025 is a `hidden beast` number, since 6 + 4 + 6 + 625 + 0 + 25 = 666.

646625025 is digitally balanced in base 6, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 195105024 + 451520001 = 13968^2 + 21249^2 .

It is not a de Polignac number, because 646625025 - 2³ = 646625017 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (646625027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 157636 + ... + 161685.

Almost surely, 2^646625025 is an apocalyptic number.

It is an amenable number.

646625025 is a deficient number, since it is larger than the sum of its proper divisors (551151797).

646625025 is a wasteful number, since it uses less digits than its factorization.

646625025 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 319343 (or 319329 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

The square root of 646625025 is about 25428.8227214710. The cubic root of 646625025 is about 864.7372541108.

The spelling of 646625025 in words is "six hundred forty-six million, six hundred twenty-five thousand, twenty-five".