2643664 has 10 divisors (see below), whose sum is σ = 5122130. Its totient is φ = 1321824.

The previous prime is 2643661. The next prime is 2643671. The reversal of 2643664 is 4663462.

It can be written as a sum of positive squares in only one way, i.e., 2016400 + 627264 = 1420^2 + 792^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2643661) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82599 + ... + 82630.

It is an arithmetic number, because the mean of its divisors is an integer number (512213).

2^2643664 is an apocalyptic number.

It is an amenable number.

2643664 is a deficient number, since it is larger than the sum of its proper divisors (2478466).

2643664 is a wasteful number, since it uses less digits than its factorization.

2643664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 165237 (or 165231 counting only the distinct ones).

The product of its digits is 20736, while the sum is 31.

The square root of 2643664 is about 1625.9348080412. The cubic root of 2643664 is about 138.2723739087.

The spelling of 2643664 in words is "two million, six hundred forty-three thousand, six hundred sixty-four".