6639960 has 32 divisors (see below), whose sum is σ = 19920240. Its totient is φ = 1770624.

The previous prime is 6639943. The next prime is 6639989. The reversal of 6639960 is 699366.

6639960 is nontrivially palindromic in base 14.

It is an Ulam number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27547 + ... + 27786.

Almost surely, 2^6639960 is an apocalyptic number.

6639960 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6639960 is an abundant number, since it is smaller than the sum of its proper divisors (13280280).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6639960 is a wasteful number, since it uses less digits than its factorization.

6639960 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 55347 (or 55343 counting only the distinct ones).

The product of its (nonzero) digits is 52488, while the sum is 39.

The square root of 6639960 is about 2576.8119838281. The cubic root of 6639960 is about 187.9555500768.

The spelling of 6639960 in words is "six million, six hundred thirty-nine thousand, nine hundred sixty".