2640636 has 18 divisors (see below), whose sum is σ = 6675032. Its totient is φ = 880200.

The previous prime is 2640581. The next prime is 2640643. The reversal of 2640636 is 6360462.

2640636 is a `hidden beast` number, since 26 + 4 + 0 + 636 = 666.

2640636 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (18).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 36640 + ... + 36711.

2^2640636 is an apocalyptic number.

It is an amenable number.

2640636 is an abundant number, since it is smaller than the sum of its proper divisors (4034396).

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

2640636 is a wasteful number, since it uses less digits than its factorization.

2640636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73361 (or 73356 counting only the distinct ones).

The product of its (nonzero) digits is 5184, while the sum is 27.

The square root of 2640636 is about 1625.0033846119. The cubic root of 2640636 is about 138.2195622676.

The spelling of 2640636 in words is "two million, six hundred forty thousand, six hundred thirty-six".