638651813083633 has 24 divisors (see below), whose sum is σ = 685378024499168. Its totient is φ = 594734148150912.

The previous prime is 638651813083631. The next prime is 638651813083639. The reversal of 638651813083633 is 336380318156836.

It is not a de Polignac number, because 638651813083633 - 2¹ = 638651813083631 is a prime.

It is a super-2 number, since 2×638651813083633² (a number of 30 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (638651813083631) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38743560 + ... + 52710217.

Almost surely, 2^{638651813083633} is an apocalyptic number.

It is an amenable number.

638651813083633 is a deficient number, since it is larger than the sum of its proper divisors (46726211415535).

638651813083633 is a wasteful number, since it uses less digits than its factorization.

638651813083633 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 91454173 (or 91454150 counting only the distinct ones).

The product of its (nonzero) digits is 134369280, while the sum is 64.

The spelling of 638651813083633 in words is "six hundred thirty-eight trillion, six hundred fifty-one billion, eight hundred thirteen million, eighty-three thousand, six hundred thirty-three".