644283 has 12 divisors (see below), whose sum is σ = 985608. Its totient is φ = 404160.

The previous prime is 644261. The next prime is 644291. The reversal of 644283 is 382446.

It is a de Polignac number, because none of the positive numbers 2^k-644283 is a prime.

644283 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (644383) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1953 + ... + 2258.

It is an arithmetic number, because the mean of its divisors is an integer number (82134).

2⁶⁴⁴²⁸³ is an apocalyptic number.

644283 is a deficient number, since it is larger than the sum of its proper divisors (341325).

644283 is a wasteful number, since it uses less digits than its factorization.

644283 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4234 (or 4231 counting only the distinct ones).

The product of its digits is 4608, while the sum is 27.

The square root of 644283 is about 802.6724113859. The cubic root of 644283 is about 86.3691987687.

The spelling of 644283 in words is "six hundred forty-four thousand, two hundred eighty-three".