638835274180 has 96 divisors (see below), whose sum is σ = 1434961301760. Its totient is φ = 238060339200.

The previous prime is 638835274171. The next prime is 638835274183. The reversal of 638835274180 is 81472538836.

It is a super-2 number, since 2×638835274180² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (638835274183) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 14507236 + ... + 14551204.

It is an arithmetic number, because the mean of its divisors is an integer number (14947513560).

Almost surely, 2^638835274180 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 638835274180, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (717480650880).

638835274180 is an abundant number, since it is smaller than the sum of its proper divisors (796126027580).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

638835274180 is a wasteful number, since it uses less digits than its factorization.

638835274180 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44429 (or 44427 counting only the distinct ones).

The product of its (nonzero) digits is 7741440, while the sum is 55.

The spelling of 638835274180 in words is "six hundred thirty-eight billion, eight hundred thirty-five million, two hundred seventy-four thousand, one hundred eighty".