638353694 has 8 divisors (see below), whose sum is σ = 1044578808. Its totient is φ = 290160760.

The previous prime is 638353693. The next prime is 638353721. The reversal of 638353694 is 496353836.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638353693) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14508017 + ... + 14508060.

It is an arithmetic number, because the mean of its divisors is an integer number (130572351).

Almost surely, 2^638353694 is an apocalyptic number.

638353694 is a deficient number, since it is larger than the sum of its proper divisors (406225114).

638353694 is a wasteful number, since it uses less digits than its factorization.

638353694 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29016090.

The product of its digits is 1399680, while the sum is 47.

The square root of 638353694 is about 25265.6623503125. The cubic root of 638353694 is about 861.0343126027.

The spelling of 638353694 in words is "six hundred thirty-eight million, three hundred fifty-three thousand, six hundred ninety-four".