639286253 has 4 divisors (see below), whose sum is σ = 642102720. Its totient is φ = 636469788.

The previous prime is 639286243. The next prime is 639286261. The reversal of 639286253 is 352682936.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 639286253 - 2⁶ = 639286189 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639286243) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1407893 + ... + 1408346.

It is an arithmetic number, because the mean of its divisors is an integer number (160525680).

Almost surely, 2^639286253 is an apocalyptic number.

It is an amenable number.

639286253 is a deficient number, since it is larger than the sum of its proper divisors (2816467).

639286253 is a wasteful number, since it uses less digits than its factorization.

639286253 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2816466.

The product of its digits is 466560, while the sum is 44.

The square root of 639286253 is about 25284.1106824029. The cubic root of 639286253 is about 861.4533982443.

The spelling of 639286253 in words is "six hundred thirty-nine million, two hundred eighty-six thousand, two hundred fifty-three".