645865952 has 24 divisors (see below), whose sum is σ = 1276884000. Its totient is φ = 321577984.

The previous prime is 645865951. The next prime is 645866009. The reversal of 645865952 is 259568546.

645865952 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 645865952.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645865951) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 34577 + ... + 49872.

It is an arithmetic number, because the mean of its divisors is an integer number (53203500).

Almost surely, 2^645865952 is an apocalyptic number.

It is an amenable number.

645865952 is a deficient number, since it is larger than the sum of its proper divisors (631018048).

645865952 is a wasteful number, since it uses less digits than its factorization.

645865952 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84698 (or 84690 counting only the distinct ones).

The product of its digits is 2592000, while the sum is 50.

The square root of 645865952 is about 25413.8928934549. The cubic root of 645865952 is about 864.3987499842.

The spelling of 645865952 in words is "six hundred forty-five million, eight hundred sixty-five thousand, nine hundred fifty-two".