638357265164 has 24 divisors (see below), whose sum is σ = 1153389783168. Its totient is φ = 308821403520.

The previous prime is 638357265163. The next prime is 638357265191. The reversal of 638357265164 is 461562753836.

It is a happy number.

It is a super-2 number, since 2×638357265164² (a number of 24 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (638357265163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 122552 + ... + 1136544.

It is an arithmetic number, because the mean of its divisors is an integer number (48057907632).

Almost surely, 2^638357265164 is an apocalyptic number.

It is an amenable number.

638357265164 is a deficient number, since it is larger than the sum of its proper divisors (515032518004).

638357265164 is a wasteful number, since it uses less digits than its factorization.

638357265164 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1019105 (or 1019103 counting only the distinct ones).

The product of its digits is 21772800, while the sum is 56.

The spelling of 638357265164 in words is "six hundred thirty-eight billion, three hundred fifty-seven million, two hundred sixty-five thousand, one hundred sixty-four".