638768783055 has 64 divisors (see below), whose sum is σ = 1148805245952. Its totient is φ = 300718725120.

The previous prime is 638768783041. The next prime is 638768783071. The reversal of 638768783055 is 550387867836.

It is not a de Polignac number, because 638768783055 - 2³³ = 630178848463 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 19147740 + ... + 19181070.

It is an arithmetic number, because the mean of its divisors is an integer number (17950081968).

Almost surely, 2^638768783055 is an apocalyptic number.

638768783055 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

638768783055 is a deficient number, since it is larger than the sum of its proper divisors (510036462897).

638768783055 is a wasteful number, since it uses less digits than its factorization.

638768783055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37648.

The product of its (nonzero) digits is 203212800, while the sum is 66.

The spelling of 638768783055 in words is "six hundred thirty-eight billion, seven hundred sixty-eight million, seven hundred eighty-three thousand, fifty-five".