645752 has 16 divisors (see below), whose sum is σ = 1234440. Its totient is φ = 316576.

The previous prime is 645751. The next prime is 645763. The reversal of 645752 is 257546.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645751) 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 3 ways as a sum of consecutive naturals, for example, 338 + ... + 1185.

2⁶⁴⁵⁷⁵² is an apocalyptic number.

It is an amenable number.

645752 is a deficient number, since it is larger than the sum of its proper divisors (588688).

645752 is a wasteful number, since it uses less digits than its factorization.

645752 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1582 (or 1578 counting only the distinct ones).

The product of its digits is 8400, while the sum is 29.

The square root of 645752 is about 803.5869585801. The cubic root of 645752 is about 86.4347910869.

The spelling of 645752 in words is "six hundred forty-five thousand, seven hundred fifty-two".