645305884 has 6 divisors (see below), whose sum is σ = 1129285304. Its totient is φ = 322652940.

The previous prime is 645305879. The next prime is 645305887. The reversal of 645305884 is 488503546.

645305884 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 645305884.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645305887) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 80663232 + ... + 80663239.

Almost surely, 2^645305884 is an apocalyptic number.

It is an amenable number.

645305884 is a deficient number, since it is larger than the sum of its proper divisors (483979420).

645305884 is a wasteful number, since it uses less digits than its factorization.

645305884 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 161326475 (or 161326473 counting only the distinct ones).

The product of its (nonzero) digits is 460800, while the sum is 43.

The square root of 645305884 is about 25402.8715699623. The cubic root of 645305884 is about 864.1488208867.

The spelling of 645305884 in words is "six hundred forty-five million, three hundred five thousand, eight hundred eighty-four".