638351770642 has 8 divisors (see below), whose sum is σ = 957532340736. Its totient is φ = 319174323732.

The previous prime is 638351770591. The next prime is 638351770657. The reversal of 638351770642 is 246077153836.

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

It is a self number, because there is not a number n which added to its sum of digits gives 638351770642.

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, 176178 + ... + 1143565.

It is an arithmetic number, because the mean of its divisors is an integer number (119691542592).

Almost surely, 2^638351770642 is an apocalyptic number.

638351770642 is a deficient number, since it is larger than the sum of its proper divisors (319180570094).

638351770642 is a wasteful number, since it uses less digits than its factorization.

638351770642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1561592.

The product of its (nonzero) digits is 5080320, while the sum is 52.

The spelling of 638351770642 in words is "six hundred thirty-eight billion, three hundred fifty-one million, seven hundred seventy thousand, six hundred forty-two".