645502 has 32 divisors (see below), whose sum is σ = 1187424. Its totient is φ = 259200.

The previous prime is 645499. The next prime is 645503. The reversal of 645502 is 205546.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10552 + ... + 10612.

It is an arithmetic number, because the mean of its divisors is an integer number (37107).

2⁶⁴⁵⁵⁰² is an apocalyptic number.

645502 is a deficient number, since it is larger than the sum of its proper divisors (541922).

645502 is a wasteful number, since it uses less digits than its factorization.

645502 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 124.

The product of its (nonzero) digits is 1200, while the sum is 22.

The square root of 645502 is about 803.4313909725. The cubic root of 645502 is about 86.4236353662.

The spelling of 645502 in words is "six hundred forty-five thousand, five hundred two".