640883 has 4 divisors (see below), whose sum is σ = 678600. Its totient is φ = 603168.

The previous prime is 640873. The next prime is 640891. The reversal of 640883 is 388046.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 640883 - 2¹⁸ = 378739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (640853) 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, 18833 + ... + 18866.

It is an arithmetic number, because the mean of its divisors is an integer number (169650).

2⁶⁴⁰⁸⁸³ is an apocalyptic number.

640883 is a deficient number, since it is larger than the sum of its proper divisors (37717).

640883 is a wasteful number, since it uses less digits than its factorization.

640883 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37716.

The product of its (nonzero) digits is 4608, while the sum is 29.

The square root of 640883 is about 800.5516847774. The cubic root of 640883 is about 86.2170020098.

The spelling of 640883 in words is "six hundred forty thousand, eight hundred eighty-three".