637864161 has 16 divisors (see below), whose sum is σ = 928827648. Its totient is φ = 386157200.

The previous prime is 637864121. The next prime is 637864177. The reversal of 637864161 is 161468736.

It is not a de Polignac number, because 637864161 - 2²⁵ = 604309729 is a prime.

It is not an unprimeable number, because it can be changed into a prime (637864111) 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, 21046 + ... + 41456.

It is an arithmetic number, because the mean of its divisors is an integer number (58051728).

Almost surely, 2^637864161 is an apocalyptic number.

It is an amenable number.

637864161 is a deficient number, since it is larger than the sum of its proper divisors (290963487).

637864161 is a wasteful number, since it uses less digits than its factorization.

637864161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21372.

The product of its digits is 145152, while the sum is 42.

The square root of 637864161 is about 25255.9727787310. The cubic root of 637864161 is about 860.8141564384.

The spelling of 637864161 in words is "six hundred thirty-seven million, eight hundred sixty-four thousand, one hundred sixty-one".