639375 has 40 divisors (see below), whose sum is σ = 1199616. Its totient is φ = 300000.

The previous prime is 639371. The next prime is 639391. The reversal of 639375 is 573936.

639375 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 639375 - 2² = 639371 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (639371) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 20610 + ... + 20640.

2⁶³⁹³⁷⁵ is an apocalyptic number.

639375 is a deficient number, since it is larger than the sum of its proper divisors (560241).

639375 is a wasteful number, since it uses less digits than its factorization.

639375 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65 (or 50 counting only the distinct ones).

The product of its digits is 17010, while the sum is 33.

The square root of 639375 is about 799.6092795860. The cubic root of 639375 is about 86.1493259296.

The spelling of 639375 in words is "six hundred thirty-nine thousand, three hundred seventy-five".