639574 has 16 divisors (see below), whose sum is σ = 1094688. Its totient is φ = 277632.

The previous prime is 639571. The next prime is 639577. The reversal of 639574 is 475936.

It is an interprime number because it is at equal distance from previous prime (639571) and next prime (639577).

It is a Harshad number since it is a multiple of its sum of digits (34).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639571) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 282 + ... + 1165.

It is an arithmetic number, because the mean of its divisors is an integer number (68418).

2⁶³⁹⁵⁷⁴ is an apocalyptic number.

639574 is a deficient number, since it is larger than the sum of its proper divisors (455114).

639574 is a wasteful number, since it uses less digits than its factorization.

639574 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1479.

The product of its digits is 22680, while the sum is 34.

The square root of 639574 is about 799.7337056796. The cubic root of 639574 is about 86.1582627494.

The spelling of 639574 in words is "six hundred thirty-nine thousand, five hundred seventy-four".