638862005181 has 16 divisors (see below), whose sum is σ = 863885979648. Its totient is φ = 419874025200.

The previous prime is 638862005147. The next prime is 638862005233. The reversal of 638862005181 is 181500268836.

It is not a de Polignac number, because 638862005181 - 2¹⁷ = 638861874109 is a prime.

It is a super-2 number, since 2×638862005181² (a number of 24 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 638862005181.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638862005381) 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, 2548536 + ... + 2787966.

It is an arithmetic number, because the mean of its divisors is an integer number (53992873728).

Almost surely, 2^638862005181 is an apocalyptic number.

It is an amenable number.

638862005181 is a deficient number, since it is larger than the sum of its proper divisors (225023974467).

638862005181 is a wasteful number, since it uses less digits than its factorization.

638862005181 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 252032.

The product of its (nonzero) digits is 552960, while the sum is 48.

The spelling of 638862005181 in words is "six hundred thirty-eight billion, eight hundred sixty-two million, five thousand, one hundred eighty-one".