639369 has 12 divisors (see below), whose sum is σ = 972400. Its totient is φ = 403704.

The previous prime is 639361. The next prime is 639371. The reversal of 639369 is 963936.

It is not a de Polignac number, because 639369 - 2³ = 639361 is a prime.

It is a super-2 number, since 2×639369² = 817585436322, which contains 22 as substring.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 639369.

It is not an unprimeable number, because it can be changed into a prime (639361) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1699 + ... + 2040.

2⁶³⁹³⁶⁹ is an apocalyptic number.

It is an amenable number.

639369 is a deficient number, since it is larger than the sum of its proper divisors (333031).

639369 is a wasteful number, since it uses less digits than its factorization.

639369 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3764 (or 3761 counting only the distinct ones).

The product of its digits is 26244, while the sum is 36.

The square root of 639369 is about 799.6055277448. The cubic root of 639369 is about 86.1490564490.

The spelling of 639369 in words is "six hundred thirty-nine thousand, three hundred sixty-nine".