639265 has 16 divisors (see below), whose sum is σ = 855360. Its totient is φ = 454720.

The previous prime is 639263. The next prime is 639269. The reversal of 639265 is 562936.

It is not a de Polignac number, because 639265 - 2¹ = 639263 is a prime.

It is a d-powerful number, because it can be written as 6⁷ + 3³ + 2⁹ + 9³ + 6⁷ + 5⁷ .

It is not an unprimeable number, because it can be changed into a prime (639263) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3147 + ... + 3343.

It is an arithmetic number, because the mean of its divisors is an integer number (53460).

2⁶³⁹²⁶⁵ is an apocalyptic number.

It is an amenable number.

639265 is a deficient number, since it is larger than the sum of its proper divisors (216095).

639265 is a wasteful number, since it uses less digits than its factorization.

639265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 272.

The product of its digits is 9720, while the sum is 31.

The square root of 639265 is about 799.5404930333. The cubic root of 639265 is about 86.1443851831.

The spelling of 639265 in words is "six hundred thirty-nine thousand, two hundred sixty-five".