645942896 has 10 divisors (see below), whose sum is σ = 1251514392. Its totient is φ = 322971440.

The previous prime is 645942883. The next prime is 645942907. The reversal of 645942896 is 698249546.

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 as a sum of consecutive naturals, namely, 20185700 + ... + 20185731.

Almost surely, 2^645942896 is an apocalyptic number.

It is an amenable number.

645942896 is a deficient number, since it is larger than the sum of its proper divisors (605571496).

645942896 is a wasteful number, since it uses less digits than its factorization.

645942896 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40371439 (or 40371433 counting only the distinct ones).

The product of its digits is 3732480, while the sum is 53.

The square root of 645942896 is about 25415.4066660363. The cubic root of 645942896 is about 864.4330747829.

The spelling of 645942896 in words is "six hundred forty-five million, nine hundred forty-two thousand, eight hundred ninety-six".