2640387878 has 32 divisors (see below), whose sum is σ = 4244011200. Its totient is φ = 1227654144.

The previous prime is 2640387857. The next prime is 2640387899. The reversal of 2640387878 is 8787830462.

2640387878 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (2640387857) and next prime (2640387899).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1692863 + ... + 1694421.

It is an arithmetic number, because the mean of its divisors is an integer number (132625350).

Almost surely, 2^2640387878 is an apocalyptic number.

2640387878 is a deficient number, since it is larger than the sum of its proper divisors (1603623322).

2640387878 is a wasteful number, since it uses less digits than its factorization.

2640387878 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2144.

The product of its (nonzero) digits is 3612672, while the sum is 53.

The square root of 2640387878 is about 51384.7047086971. The cubic root of 2640387878 is about 1382.1523295851.

The spelling of 2640387878 in words is "two billion, six hundred forty million, three hundred eighty-seven thousand, eight hundred seventy-eight".