638834 has 8 divisors (see below), whose sum is σ = 1095168. Its totient is φ = 273780.

The previous prime is 638819. The next prime is 638839. The reversal of 638834 is 438836.

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 638834.

It is not an unprimeable number, because it can be changed into a prime (638839) by changing a digit.

638834 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22802 + ... + 22829.

It is an arithmetic number, because the mean of its divisors is an integer number (136896).

2⁶³⁸⁸³⁴ is an apocalyptic number.

638834 is a deficient number, since it is larger than the sum of its proper divisors (456334).

638834 is a wasteful number, since it uses less digits than its factorization.

638834 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 45640.

The product of its digits is 13824, while the sum is 32.

The square root of 638834 is about 799.2709177744. The cubic root of 638834 is about 86.1250209772.

The spelling of 638834 in words is "six hundred thirty-eight thousand, eight hundred thirty-four".