645330 has 48 divisors (see below), whose sum is σ = 1805760. Its totient is φ = 147168.

The previous prime is 645329. The next prime is 645347. The reversal of 645330 is 33546.

645330 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a nialpdrome in base 15.

It is a junction number, because it is equal to n+sod(n) for n = 645297 and 645306.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1251 + ... + 1689.

It is an arithmetic number, because the mean of its divisors is an integer number (37620).

2⁶⁴⁵³³⁰ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645330, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (902880).

645330 is an abundant number, since it is smaller than the sum of its proper divisors (1160430).

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

645330 is a wasteful number, since it uses less digits than its factorization.

645330 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 463 (or 456 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 21.

The square root of 645330 is about 803.3243429649. The cubic root of 645330 is about 86.4159585577.

Adding to 645330 its reverse (33546), we get a palindrome (678876).

The spelling of 645330 in words is "six hundred forty-five thousand, three hundred thirty".