6640606625 has 8 divisors (see below), whose sum is σ = 8287477224. Its totient is φ = 5312485200.

The previous prime is 6640606601. The next prime is 6640606631. The reversal of 6640606625 is 5266060466.

It can be written as a sum of positive squares in 4 ways, for example, as 312481 + 6640294144 = 559^2 + 81488^2 .

It is not a de Polignac number, because 6640606625 - 2¹⁸ = 6640344481 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 26562302 + ... + 26562551.

It is an arithmetic number, because the mean of its divisors is an integer number (1035934653).

Almost surely, 2^6640606625 is an apocalyptic number.

It is an amenable number.

6640606625 is a deficient number, since it is larger than the sum of its proper divisors (1646870599).

6640606625 is an equidigital number, since it uses as much as digits as its factorization.

6640606625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53124868 (or 53124858 counting only the distinct ones).

The product of its (nonzero) digits is 311040, while the sum is 41.

The square root of 6640606625 is about 81489.9173211018. The cubic root of 6640606625 is about 1879.6165115832.

The spelling of 6640606625 in words is "six billion, six hundred forty million, six hundred six thousand, six hundred twenty-five".