645543524 has 12 divisors (see below), whose sum is σ = 1157255148. Its totient is φ = 314899200.

The previous prime is 645543517. The next prime is 645543581. The reversal of 645543524 is 425345546.

645543524 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 180364900 + 465178624 = 13430^2 + 21568^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1967957 + ... + 1968284.

It is an arithmetic number, because the mean of its divisors is an integer number (96437929).

Almost surely, 2^645543524 is an apocalyptic number.

It is an amenable number.

645543524 is a deficient number, since it is larger than the sum of its proper divisors (511711624).

645543524 is a wasteful number, since it uses less digits than its factorization.

645543524 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3936286 (or 3936284 counting only the distinct ones).

The product of its digits is 288000, while the sum is 38.

The square root of 645543524 is about 25407.5485633699. The cubic root of 645543524 is about 864.2548848624.

The spelling of 645543524 in words is "six hundred forty-five million, five hundred forty-three thousand, five hundred twenty-four".