645132 has 24 divisors (see below), whose sum is σ = 1547056. Its totient is φ = 209088.

The previous prime is 645131. The next prime is 645137. The reversal of 645132 is 231546.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 645099 and 645108.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 645132.

It is not an unprimeable number, because it can be changed into a prime (645131) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 283 + ... + 1170.

2⁶⁴⁵¹³² is an apocalyptic number.

It is an amenable number.

645132 is an abundant number, since it is smaller than the sum of its proper divisors (901924).

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

645132 is a wasteful number, since it uses less digits than its factorization.

645132 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1497 (or 1495 counting only the distinct ones).

The product of its digits is 720, while the sum is 21.

The square root of 645132 is about 803.2010956168. The cubic root of 645132 is about 86.4071196122.

Adding to 645132 its reverse (231546), we get a palindrome (876678).

It can be divided in two parts, 645 and 132, that added together give a palindrome (777).

The spelling of 645132 in words is "six hundred forty-five thousand, one hundred thirty-two".