638909602 has 8 divisors (see below), whose sum is σ = 964103616. Its totient is φ = 317541732.

The previous prime is 638909591. The next prime is 638909603. The reversal of 638909602 is 206909836.

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

It is not an unprimeable number, because it can be changed into a prime (638909603) 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, 956118 + ... + 956785.

It is an arithmetic number, because the mean of its divisors is an integer number (120512952).

Almost surely, 2^638909602 is an apocalyptic number.

638909602 is a deficient number, since it is larger than the sum of its proper divisors (325194014).

638909602 is a wasteful number, since it uses less digits than its factorization.

638909602 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1913072.

The product of its (nonzero) digits is 139968, while the sum is 43.

The square root of 638909602 is about 25276.6612114812. The cubic root of 638909602 is about 861.2841829536.

The spelling of 638909602 in words is "six hundred thirty-eight million, nine hundred nine thousand, six hundred two".