638660463608 has 16 divisors (see below), whose sum is σ = 1197542805480. Its totient is φ = 319315715488.

The previous prime is 638660463593. The next prime is 638660463613. The reversal of 638660463608 is 806364066836.

It is a congruent number.

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 3 ways as a sum of consecutive naturals, for example, 1626410 + ... + 1980537.

Almost surely, 2^638660463608 is an apocalyptic number.

It is an amenable number.

638660463608 is a deficient number, since it is larger than the sum of its proper divisors (558882341872).

638660463608 is a wasteful number, since it uses less digits than its factorization.

638660463608 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3629086 (or 3629082 counting only the distinct ones).

The product of its (nonzero) digits is 17915904, while the sum is 56.

The spelling of 638660463608 in words is "six hundred thirty-eight billion, six hundred sixty million, four hundred sixty-three thousand, six hundred eight".