638825565337 has 4 divisors (see below), whose sum is σ = 639613267216. Its totient is φ = 638037863460.

The previous prime is 638825565307. The next prime is 638825565341. The reversal of 638825565337 is 733565528836.

638825565337 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-638825565337 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (638825565307) 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, 393849723 + ... + 393851344.

It is an arithmetic number, because the mean of its divisors is an integer number (159903316804).

Almost surely, 2^638825565337 is an apocalyptic number.

It is an amenable number.

638825565337 is a deficient number, since it is larger than the sum of its proper divisors (787701879).

638825565337 is an equidigital number, since it uses as much as digits as its factorization.

638825565337 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 787701878.

The product of its digits is 108864000, while the sum is 61.

The spelling of 638825565337 in words is "six hundred thirty-eight billion, eight hundred twenty-five million, five hundred sixty-five thousand, three hundred thirty-seven".