638660463599 has 4 divisors (see below), whose sum is σ = 639036812064. Its totient is φ = 638284115136.

The previous prime is 638660463593. The next prime is 638660463613. The reversal of 638660463599 is 995364066836.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 638660463599 - 2⁴ = 638660463583 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638660463593) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 188171687 + ... + 188175080.

It is an arithmetic number, because the mean of its divisors is an integer number (159759203016).

Almost surely, 2^638660463599 is an apocalyptic number.

638660463599 is a deficient number, since it is larger than the sum of its proper divisors (376348465).

638660463599 is a wasteful number, since it uses less digits than its factorization.

638660463599 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 376348464.

The product of its (nonzero) digits is 151165440, while the sum is 65.

The spelling of 638660463599 in words is "six hundred thirty-eight billion, six hundred sixty million, four hundred sixty-three thousand, five hundred ninety-nine".