6640964 has 18 divisors (see below), whose sum is σ = 12775182. Its totient is φ = 3018400.

The previous prime is 6640939. The next prime is 6640967. The reversal of 6640964 is 4690466.

It can be written as a sum of positive squares in only one way, i.e., 4840000 + 1800964 = 2200^2 + 1342^2 .

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (6640967) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6377 + ... + 7344.

Almost surely, 2^6640964 is an apocalyptic number.

It is an amenable number.

6640964 is a deficient number, since it is larger than the sum of its proper divisors (6134218).

6640964 is a wasteful number, since it uses less digits than its factorization.

6640964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13747 (or 13734 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 35.

The square root of 6640964 is about 2577.0067908331. The cubic root of 6640964 is about 187.9650229181.

Subtracting from 6640964 its sum of digits (35), we obtain a square (6640929 = 2577²).

The spelling of 6640964 in words is "six million, six hundred forty thousand, nine hundred sixty-four".