639993355 has 8 divisors (see below), whose sum is σ = 781009200. Its totient is φ = 503316576.

The previous prime is 639993323. The next prime is 639993371. The reversal of 639993355 is 553399936.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 639993355 - 2⁵ = 639993323 is a prime.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1084440 + ... + 1085029.

It is an arithmetic number, because the mean of its divisors is an integer number (97626150).

Almost surely, 2^639993355 is an apocalyptic number.

639993355 is a deficient number, since it is larger than the sum of its proper divisors (141015845).

639993355 is a wasteful number, since it uses less digits than its factorization.

639993355 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2169533.

The product of its digits is 2952450, while the sum is 52.

The square root of 639993355 is about 25298.0899476621. The cubic root of 639993355 is about 861.7708934569.

The spelling of 639993355 in words is "six hundred thirty-nine million, nine hundred ninety-three thousand, three hundred fifty-five".