638586743807 has 4 divisors (see below), whose sum is σ = 640626957360. Its totient is φ = 636546530256.

The previous prime is 638586743803. The next prime is 638586743813. The reversal of 638586743807 is 708347685836.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 638586743807 - 2² = 638586743803 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638586743803) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1020106307 + ... + 1020106932.

It is an arithmetic number, because the mean of its divisors is an integer number (160156739340).

Almost surely, 2^638586743807 is an apocalyptic number.

638586743807 is a deficient number, since it is larger than the sum of its proper divisors (2040213553).

638586743807 is a wasteful number, since it uses less digits than its factorization.

638586743807 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2040213552.

The product of its (nonzero) digits is 162570240, while the sum is 65.

The spelling of 638586743807 in words is "six hundred thirty-eight billion, five hundred eighty-six million, seven hundred forty-three thousand, eight hundred seven".