645748 has 12 divisors (see below), whose sum is σ = 1179360. Its totient is φ = 308792.

The previous prime is 645739. The next prime is 645751. The reversal of 645748 is 847546.

It is a congruent number.

It is an unprimeable number.

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, 3418 + ... + 3601.

It is an arithmetic number, because the mean of its divisors is an integer number (98280).

2⁶⁴⁵⁷⁴⁸ is an apocalyptic number.

It is an amenable number.

645748 is a deficient number, since it is larger than the sum of its proper divisors (533612).

645748 is a wasteful number, since it uses less digits than its factorization.

645748 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7046 (or 7044 counting only the distinct ones).

The product of its digits is 26880, while the sum is 34.

The square root of 645748 is about 803.5844697354. The cubic root of 645748 is about 86.4346126181.

It can be divided in two parts, 6 and 45748, that added together give a palindrome (45754).

The spelling of 645748 in words is "six hundred forty-five thousand, seven hundred forty-eight".