638865503145 has 48 divisors (see below), whose sum is σ = 1124219416320. Its totient is φ = 335580319872.

The previous prime is 638865503131. The next prime is 638865503179. The reversal of 638865503145 is 541305568836.

It is a happy number.

638865503145 is a `hidden beast` number, since 6 + 3 + 8 + 86 + 550 + 3 + 1 + 4 + 5 = 666.

It is not a de Polignac number, because 638865503145 - 2¹¹ = 638865501097 is a prime.

It is a super-2 number, since 2×638865503145² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 638865503091 and 638865503100.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 429172 + ... + 1209098.

It is an arithmetic number, because the mean of its divisors is an integer number (23421237840).

Almost surely, 2^638865503145 is an apocalyptic number.

It is an amenable number.

638865503145 is a deficient number, since it is larger than the sum of its proper divisors (485353913175).

638865503145 is a wasteful number, since it uses less digits than its factorization.

638865503145 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 780214 (or 780211 counting only the distinct ones).

The product of its (nonzero) digits is 10368000, while the sum is 54.

The spelling of 638865503145 in words is "six hundred thirty-eight billion, eight hundred sixty-five million, five hundred three thousand, one hundred forty-five".