638840760242 has 8 divisors (see below), whose sum is σ = 967748874732. Its totient is φ = 316257802000.

The previous prime is 638840760223. The next prime is 638840760253. The reversal of 638840760242 is 242067048836.

It can be written as a sum of positive squares in 2 ways, for example, as 470707138561 + 168133621681 = 686081^2 + 410041^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1581288809 + ... + 1581289212.

Almost surely, 2^638840760242 is an apocalyptic number.

638840760242 is a deficient number, since it is larger than the sum of its proper divisors (328908114490).

638840760242 is a wasteful number, since it uses less digits than its factorization.

638840760242 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3162578124.

The product of its (nonzero) digits is 3096576, while the sum is 50.

The spelling of 638840760242 in words is "six hundred thirty-eight billion, eight hundred forty million, seven hundred sixty thousand, two hundred forty-two".