2638811666 has 16 divisors (see below), whose sum is σ = 4147469568. Its totient is φ = 1256798400.

The previous prime is 2638811657. The next prime is 2638811677. The reversal of 2638811666 is 6661188362.

It is a self number, because there is not a number n which added to its sum of digits gives 2638811666.

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, 107930 + ... + 130101.

It is an arithmetic number, because the mean of its divisors is an integer number (259216848).

Almost surely, 2^2638811666 is an apocalyptic number.

2638811666 is a deficient number, since it is larger than the sum of its proper divisors (1508657902).

2638811666 is a wasteful number, since it uses less digits than its factorization.

2638811666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 238297.

The product of its digits is 497664, while the sum is 47.

The square root of 2638811666 is about 51369.3650535025. The cubic root of 2638811666 is about 1381.8772438983.

The spelling of 2638811666 in words is "two billion, six hundred thirty-eight million, eight hundred eleven thousand, six hundred sixty-six".