638913 has 16 divisors (see below), whose sum is σ = 979200. Its totient is φ = 366480.

The previous prime is 638893. The next prime is 638923. The reversal of 638913 is 319836.

It is not a de Polignac number, because 638913 - 2¹² = 634817 is a prime.

It is not an unprimeable number, because it can be changed into a prime (638923) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 118 + ... + 1136.

It is an arithmetic number, because the mean of its divisors is an integer number (61200).

2⁶³⁸⁹¹³ is an apocalyptic number.

It is an amenable number.

638913 is a deficient number, since it is larger than the sum of its proper divisors (340287).

638913 is a wasteful number, since it uses less digits than its factorization.

638913 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1052.

The product of its digits is 3888, while the sum is 30.

The square root of 638913 is about 799.3203362858. The cubic root of 638913 is about 86.1285709846.

It can be divided in two parts, 638 and 913, that added together give a palindrome (1551).

The spelling of 638913 in words is "six hundred thirty-eight thousand, nine hundred thirteen".