639345 has 16 divisors (see below), whose sum is σ = 1169280. Its totient is φ = 292224.

The previous prime is 639337. The next prime is 639361. The reversal of 639345 is 543936.

It is a happy number.

It is not a de Polignac number, because 639345 - 2³ = 639337 is a prime.

It is an Ulam number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2940 + ... + 3149.

It is an arithmetic number, because the mean of its divisors is an integer number (73080).

2⁶³⁹³⁴⁵ is an apocalyptic number.

It is an amenable number.

639345 is a deficient number, since it is larger than the sum of its proper divisors (529935).

639345 is a wasteful number, since it uses less digits than its factorization.

639345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6104.

The product of its digits is 9720, while the sum is 30.

The square root of 639345 is about 799.5905202039. The cubic root of 639345 is about 86.1479785095.

The spelling of 639345 in words is "six hundred thirty-nine thousand, three hundred forty-five".