2640402566 has 16 divisors (see below), whose sum is σ = 4282808256. Its totient is φ = 1216104576.

The previous prime is 2640402551. The next prime is 2640402571. The reversal of 2640402566 is 6652040462.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 824561 + ... + 827756.

It is an arithmetic number, because the mean of its divisors is an integer number (267675516).

Almost surely, 2^2640402566 is an apocalyptic number.

2640402566 is a deficient number, since it is larger than the sum of its proper divisors (1642405690).

2640402566 is a wasteful number, since it uses less digits than its factorization.

2640402566 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1652383.

The product of its (nonzero) digits is 69120, while the sum is 35.

The square root of 2640402566 is about 51384.8476304056. The cubic root of 2640402566 is about 1382.1548924681.

The spelling of 2640402566 in words is "two billion, six hundred forty million, four hundred two thousand, five hundred sixty-six".