640375 has 16 divisors (see below), whose sum is σ = 823680. Its totient is φ = 496800.

The previous prime is 640369. The next prime is 640411. The reversal of 640375 is 573046.

It is not a de Polignac number, because 640375 - 2⁷ = 640247 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5821 + ... + 5929.

It is an arithmetic number, because the mean of its divisors is an integer number (51480).

2⁶⁴⁰³⁷⁵ is an apocalyptic number.

640375 is a deficient number, since it is larger than the sum of its proper divisors (183305).

640375 is a wasteful number, since it uses less digits than its factorization.

640375 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 171 (or 161 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 25.

The square root of 640375 is about 800.2343406778. The cubic root of 640375 is about 86.1942158360.

The spelling of 640375 in words is "six hundred forty thousand, three hundred seventy-five".