638617776247 has 16 divisors (see below), whose sum is σ = 699496072704. Its totient is φ = 578210560000.

The previous prime is 638617776191. The next prime is 638617776311. The reversal of 638617776247 is 742677716836.

638617776247 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 638617776247 - 2¹⁵ = 638617743479 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638617776847) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 22915872 + ... + 22943722.

It is an arithmetic number, because the mean of its divisors is an integer number (43718504544).

Almost surely, 2^638617776247 is an apocalyptic number.

638617776247 is a deficient number, since it is larger than the sum of its proper divisors (60878296457).

638617776247 is a wasteful number, since it uses less digits than its factorization.

638617776247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36230.

The product of its digits is 99574272, while the sum is 64.

The spelling of 638617776247 in words is "six hundred thirty-eight billion, six hundred seventeen million, seven hundred seventy-six thousand, two hundred forty-seven".