6639657 has 8 divisors (see below), whose sum is σ = 8867040. Its totient is φ = 4419360.

The previous prime is 6639653. The next prime is 6639679. The reversal of 6639657 is 7569366.

6639657 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 6639657 - 2² = 6639653 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6639653) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1069 + ... + 3797.

It is an arithmetic number, because the mean of its divisors is an integer number (1108380).

Almost surely, 2^6639657 is an apocalyptic number.

It is an amenable number.

6639657 is a deficient number, since it is larger than the sum of its proper divisors (2227383).

6639657 is a wasteful number, since it uses less digits than its factorization.

6639657 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3543.

The product of its digits is 204120, while the sum is 42.

The square root of 6639657 is about 2576.7531895779. The cubic root of 6639657 is about 187.9526910536.

The spelling of 6639657 in words is "six million, six hundred thirty-nine thousand, six hundred fifty-seven".