645443824 has 10 divisors (see below), whose sum is σ = 1250547440. Its totient is φ = 322721904.

The previous prime is 645443819. The next prime is 645443831. The reversal of 645443824 is 428344546.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20170104 + ... + 20170135.

It is an arithmetic number, because the mean of its divisors is an integer number (125054744).

Almost surely, 2^645443824 is an apocalyptic number.

It is an amenable number.

645443824 is a deficient number, since it is larger than the sum of its proper divisors (605103616).

645443824 is a wasteful number, since it uses less digits than its factorization.

645443824 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40340247 (or 40340241 counting only the distinct ones).

The product of its digits is 368640, while the sum is 40.

The square root of 645443824 is about 25405.5864722702. The cubic root of 645443824 is about 864.2103897225.

The spelling of 645443824 in words is "six hundred forty-five million, four hundred forty-three thousand, eight hundred twenty-four".