645115256 has 8 divisors (see below), whose sum is σ = 1209591120. Its totient is φ = 322557624.

The previous prime is 645115231. The next prime is 645115271. The reversal of 645115256 is 652511546.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40319696 + ... + 40319711.

It is an arithmetic number, because the mean of its divisors is an integer number (151198890).

Almost surely, 2^645115256 is an apocalyptic number.

It is an amenable number.

645115256 is a deficient number, since it is larger than the sum of its proper divisors (564475864).

645115256 is a wasteful number, since it uses less digits than its factorization.

645115256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80639413 (or 80639409 counting only the distinct ones).

The product of its digits is 36000, while the sum is 35.

The square root of 645115256 is about 25399.1191973265. The cubic root of 645115256 is about 864.0637205805.

The spelling of 645115256 in words is "six hundred forty-five million, one hundred fifteen thousand, two hundred fifty-six".