638604658582 has 32 divisors (see below), whose sum is σ = 1054839417984. Its totient is φ = 287546625600.

The previous prime is 638604658577. The next prime is 638604658583. The reversal of 638604658582 is 285856406836.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 638604658582.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638604658583) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1425778 + ... + 1819354.

It is an arithmetic number, because the mean of its divisors is an integer number (32963731812).

Almost surely, 2^638604658582 is an apocalyptic number.

638604658582 is a deficient number, since it is larger than the sum of its proper divisors (416234759402).

638604658582 is a wasteful number, since it uses less digits than its factorization.

638604658582 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 394284.

The product of its (nonzero) digits is 66355200, while the sum is 61.

The spelling of 638604658582 in words is "six hundred thirty-eight billion, six hundred four million, six hundred fifty-eight thousand, five hundred eighty-two".