3638644387340 has 24 divisors (see below), whose sum is σ = 7641921663600. Its totient is φ = 1455311383488.

The previous prime is 3638644387283. The next prime is 3638644387387. The reversal of 3638644387340 is 437834468363.

It is a self number, because there is not a number n which added to its sum of digits gives 3638644387340.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8944262 + ... + 9342221.

It is an arithmetic number, because the mean of its divisors is an integer number (318413402650).

Almost surely, 2^{3638644387340} is an apocalyptic number.

It is an amenable number.

3638644387340 is an abundant number, since it is smaller than the sum of its proper divisors (4003277276260).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

3638644387340 is a wasteful number, since it uses less digits than its factorization.

3638644387340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18296441 (or 18296439 counting only the distinct ones).

The product of its (nonzero) digits is 83607552, while the sum is 59.

The spelling of 3638644387340 in words is "three trillion, six hundred thirty-eight billion, six hundred forty-four million, three hundred eighty-seven thousand, three hundred forty".