6640959 has 16 divisors (see below), whose sum is σ = 9741312. Its totient is φ = 3998688.

The previous prime is 6640939. The next prime is 6640967. The reversal of 6640959 is 9590466.

It is not a de Polignac number, because 6640959 - 2⁵ = 6640927 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6640939) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22 + ... + 3644.

It is an arithmetic number, because the mean of its divisors is an integer number (608832).

Almost surely, 2^6640959 is an apocalyptic number.

6640959 is a deficient number, since it is larger than the sum of its proper divisors (3100353).

6640959 is a wasteful number, since it uses less digits than its factorization.

6640959 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3686.

The product of its (nonzero) digits is 58320, while the sum is 39.

The square root of 6640959 is about 2577.0058207152. The cubic root of 6640959 is about 187.9649757449.

The spelling of 6640959 in words is "six million, six hundred forty thousand, nine hundred fifty-nine".