638589 has 16 divisors (see below), whose sum is σ = 995328. Its totient is φ = 356592.

The previous prime is 638587. The next prime is 638621. The reversal of 638589 is 985836.

It is not a de Polignac number, because 638589 - 2¹ = 638587 is a prime.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638581) 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, 664 + ... + 1310.

It is an arithmetic number, because the mean of its divisors is an integer number (62208).

2⁶³⁸⁵⁸⁹ is an apocalyptic number.

It is an amenable number.

638589 is a deficient number, since it is larger than the sum of its proper divisors (356739).

638589 is a wasteful number, since it uses less digits than its factorization.

638589 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 704.

The product of its digits is 51840, while the sum is 39.

The square root of 638589 is about 799.1176383988. The cubic root of 638589 is about 86.1140095991.

The spelling of 638589 in words is "six hundred thirty-eight thousand, five hundred eighty-nine".