638865858141 has 96 divisors (see below), whose sum is σ = 1103145039360. Its totient is φ = 348728371200.

The previous prime is 638865858121. The next prime is 638865858233. The reversal of 638865858141 is 141858568836.

638865858141 is a `hidden beast` number, since 6 + 3 + 8 + 8 + 6 + 5 + 8 + 581 + 41 = 666.

It is not a de Polignac number, because 638865858141 - 2¹³ = 638865849949 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638865858121) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 23664871 + ... + 23691851.

It is an arithmetic number, because the mean of its divisors is an integer number (11491094160).

Almost surely, 2^638865858141 is an apocalyptic number.

It is an amenable number.

638865858141 is a deficient number, since it is larger than the sum of its proper divisors (464279181219).

638865858141 is a wasteful number, since it uses less digits than its factorization.

638865858141 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27227 (or 27224 counting only the distinct ones).

The product of its digits is 44236800, while the sum is 63.

The spelling of 638865858141 in words is "six hundred thirty-eight billion, eight hundred sixty-five million, eight hundred fifty-eight thousand, one hundred forty-one".