645258 has 32 divisors (see below), whose sum is σ = 1374912. Its totient is φ = 201600.

The previous prime is 645257. The next prime is 645313. The reversal of 645258 is 852546.

It is an Ulam number.

Its product of digits (9600) is a multiple of the sum of its prime divisors (150).

It is not an unprimeable number, because it can be changed into a prime (645257) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10548 + ... + 10608.

It is an arithmetic number, because the mean of its divisors is an integer number (42966).

2⁶⁴⁵²⁵⁸ is an apocalyptic number.

645258 is an abundant number, since it is smaller than the sum of its proper divisors (729654).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

645258 is a wasteful number, since it uses less digits than its factorization.

645258 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 150.

The product of its digits is 9600, while the sum is 30.

The square root of 645258 is about 803.2795279353. The cubic root of 645258 is about 86.4127446049.

It can be divided in two parts, 645 and 258, that added together give a triangular number (903 = T₄₂).

The spelling of 645258 in words is "six hundred forty-five thousand, two hundred fifty-eight".