645256577 has 8 divisors (see below), whose sum is σ = 738672000. Its totient is φ = 552150144.

The previous prime is 645256567. The next prime is 645256603. The reversal of 645256577 is 775652546.

645256577 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 645256577 - 2¹² = 645252481 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645256517) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 72752 + ... + 81137.

It is an arithmetic number, because the mean of its divisors is an integer number (92334000).

Almost surely, 2^645256577 is an apocalyptic number.

It is an amenable number.

645256577 is a deficient number, since it is larger than the sum of its proper divisors (93415423).

645256577 is a wasteful number, since it uses less digits than its factorization.

645256577 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 154495.

The product of its digits is 1764000, while the sum is 47.

The square root of 645256577 is about 25401.9010509056. The cubic root of 645256577 is about 864.1268108229.

The spelling of 645256577 in words is "six hundred forty-five million, two hundred fifty-six thousand, five hundred seventy-seven".