6640925 has 12 divisors (see below), whose sum is σ = 8317920. Its totient is φ = 5259120.

The previous prime is 6640903. The next prime is 6640927. The reversal of 6640925 is 5290466.

It is not a de Polignac number, because 6640925 - 2¹⁸ = 6378781 is a prime.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a junction number, because it is equal to n+sod(n) for n = 6640891 and 6640900.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6640927) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1286 + ... + 3864.

It is an arithmetic number, because the mean of its divisors is an integer number (693160).

Almost surely, 2^6640925 is an apocalyptic number.

It is an amenable number.

6640925 is a deficient number, since it is larger than the sum of its proper divisors (1676995).

6640925 is a wasteful number, since it uses less digits than its factorization.

6640925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2692 (or 2687 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 32.

The square root of 6640925 is about 2576.9992239036. Note that the first 3 decimals coincide. The cubic root of 6640925 is about 187.9646549669.

The spelling of 6640925 in words is "six million, six hundred forty thousand, nine hundred twenty-five".