638575 has 24 divisors (see below), whose sum is σ = 937440. Its totient is φ = 422400.

The previous prime is 638567. The next prime is 638581. The reversal of 638575 is 575836.

It is a happy number.

It is not a de Polignac number, because 638575 - 2³ = 638567 is a prime.

It is a hoax number, since the sum of its digits (34) coincides with the sum of the digits of its distinct prime factors.

638575 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 638575.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 7131 + ... + 7219.

It is an arithmetic number, because the mean of its divisors is an integer number (39060).

2⁶³⁸⁵⁷⁵ is an apocalyptic number.

638575 is a deficient number, since it is larger than the sum of its proper divisors (298865).

638575 is a wasteful number, since it uses less digits than its factorization.

638575 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 147 (or 142 counting only the distinct ones).

The product of its digits is 25200, while the sum is 34.

The square root of 638575 is about 799.1088786893. The cubic root of 638575 is about 86.1133802925.

It can be divided in two parts, 63 and 8575, that multiplied together give a square (540225 = 735²).

The spelling of 638575 in words is "six hundred thirty-eight thousand, five hundred seventy-five".