638265 has 16 divisors (see below), whose sum is σ = 1081728. Its totient is φ = 320256.

The previous prime is 638263. The next prime is 638269. The reversal of 638265 is 562836.

It is not a de Polignac number, because 638265 - 2¹ = 638263 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (638263) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 997 + ... + 1506.

It is an arithmetic number, because the mean of its divisors is an integer number (67608).

2⁶³⁸²⁶⁵ is an apocalyptic number.

It is an amenable number.

638265 is a deficient number, since it is larger than the sum of its proper divisors (443463).

638265 is a wasteful number, since it uses less digits than its factorization.

638265 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2528.

The product of its digits is 8640, while the sum is 30.

The square root of 638265 is about 798.9148890839. The cubic root of 638265 is about 86.0994432875.

It can be divided in two parts, 638 and 265, that added together give a triangular number (903 = T₄₂).

The spelling of 638265 in words is "six hundred thirty-eight thousand, two hundred sixty-five".