2640664 has 16 divisors (see below), whose sum is σ = 5332320. Its totient is φ = 1218720.

The previous prime is 2640643. The next prime is 2640683. The reversal of 2640664 is 4660462.

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 3 ways as a sum of consecutive naturals, for example, 12592 + ... + 12799.

It is an arithmetic number, because the mean of its divisors is an integer number (333270).

2^2640664 is an apocalyptic number.

It is an amenable number.

2640664 is an abundant number, since it is smaller than the sum of its proper divisors (2691656).

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

2640664 is a wasteful number, since it uses less digits than its factorization.

2640664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25410 (or 25406 counting only the distinct ones).

The product of its (nonzero) digits is 6912, while the sum is 28.

The square root of 2640664 is about 1625.0119999557. The cubic root of 2640664 is about 138.2200508032.

The spelling of 2640664 in words is "two million, six hundred forty thousand, six hundred sixty-four".