645468 has 36 divisors (see below), whose sum is σ = 1600200. Its totient is φ = 202464.

The previous prime is 645467. The next prime is 645481. The reversal of 645468 is 864546.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645467) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4258 + ... + 4406.

It is an arithmetic number, because the mean of its divisors is an integer number (44450).

2⁶⁴⁵⁴⁶⁸ is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645468, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (800100).

645468 is an abundant number, since it is smaller than the sum of its proper divisors (954732).

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

645468 is a wasteful number, since it uses less digits than its factorization.

645468 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 194 (or 173 counting only the distinct ones).

The product of its digits is 23040, while the sum is 33.

The square root of 645468 is about 803.4102314509. The cubic root of 645468 is about 86.4221179657.

The spelling of 645468 in words is "six hundred forty-five thousand, four hundred sixty-eight".