645813575 has 24 divisors (see below), whose sum is σ = 877610496. Its totient is φ = 467532000.

The previous prime is 645813559. The next prime is 645813583. The reversal of 645813575 is 575318546.

It is not a de Polignac number, because 645813575 - 2⁴ = 645813559 is a prime.

It is a Duffinian number.

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 in 23 ways as a sum of consecutive naturals, for example, 56060 + ... + 66590.

It is an arithmetic number, because the mean of its divisors is an integer number (36567104).

Almost surely, 2^645813575 is an apocalyptic number.

645813575 is a deficient number, since it is larger than the sum of its proper divisors (231796921).

645813575 is a wasteful number, since it uses less digits than its factorization.

645813575 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10775 (or 10770 counting only the distinct ones).

The product of its digits is 504000, while the sum is 44.

The square root of 645813575 is about 25412.8623928907. The cubic root of 645813575 is about 864.3753829903.

The spelling of 645813575 in words is "six hundred forty-five million, eight hundred thirteen thousand, five hundred seventy-five".