638053853807 has 4 divisors (see below), whose sum is σ = 645741249720. Its totient is φ = 630366457896.

The previous prime is 638053853791. The next prime is 638053853849. The reversal of 638053853807 is 708358350836.

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 638053853807 - 2⁴ = 638053853791 is a prime.

It is a super-2 number, since 2×638053853807² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638053853887) 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, 3843697832 + ... + 3843697997.

It is an arithmetic number, because the mean of its divisors is an integer number (161435312430).

Almost surely, 2^638053853807 is an apocalyptic number.

638053853807 is a deficient number, since it is larger than the sum of its proper divisors (7687395913).

638053853807 is an equidigital number, since it uses as much as digits as its factorization.

638053853807 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7687395912.

The product of its (nonzero) digits is 14515200, while the sum is 56.

The spelling of 638053853807 in words is "six hundred thirty-eight billion, fifty-three million, eight hundred fifty-three thousand, eight hundred seven".