638836 has 12 divisors (see below), whose sum is σ = 1219680. Its totient is φ = 290360.

The previous prime is 638819. The next prime is 638839.

638836 is nontrivially palindromic in base 10.

It is a super-2 number, since 2×638836² = 816222869792, which contains 22 as substring.

It is a d-powerful number, because it can be written as 6⁵ + 3⁹ + 8³ + 8⁵ + 3¹² + 6⁶ .

It is a nialpdrome in base 15.

It is a congruent number.

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

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, 7216 + ... + 7303.

It is an arithmetic number, because the mean of its divisors is an integer number (101640).

2⁶³⁸⁸³⁶ is an apocalyptic number.

It is an amenable number.

638836 is a deficient number, since it is larger than the sum of its proper divisors (580844).

638836 is a wasteful number, since it uses less digits than its factorization.

638836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14534 (or 14532 counting only the distinct ones).

The product of its digits is 20736, while the sum is 34.

The square root of 638836 is about 799.2721689137. The cubic root of 638836 is about 86.1251108544.

The spelling of 638836 in words is "six hundred thirty-eight thousand, eight hundred thirty-six".