638840760220 has 48 divisors (see below), whose sum is σ = 1446449292288. Its totient is φ = 235604344320.

The previous prime is 638840760169. The next prime is 638840760223. The reversal of 638840760220 is 22067048836.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638840760223) 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, 1210716 + ... + 1656355.

It is an arithmetic number, because the mean of its divisors is an integer number (30134360256).

Almost surely, 2^638840760220 is an apocalyptic number.

It is an amenable number.

638840760220 is an abundant number, since it is smaller than the sum of its proper divisors (807608532068).

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

638840760220 is a wasteful number, since it uses less digits than its factorization.

638840760220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2867950 (or 2867948 counting only the distinct ones).

The product of its (nonzero) digits is 774144, while the sum is 46.

The spelling of 638840760220 in words is "six hundred thirty-eight billion, eight hundred forty million, seven hundred sixty thousand, two hundred twenty".