813125645 has 8 divisors (see below), whose sum is σ = 975910680. Its totient is φ = 650393920.

The previous prime is 813125639. The next prime is 813125659. The reversal of 813125645 is 546521318.

It can be written as a sum of positive squares in 4 ways, for example, as 351262564 + 461863081 = 18742^2 + 21491^2 .

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

It is not a de Polignac number, because 813125645 - 2⁶ = 813125581 is a prime.

It is a super-3 number, since 3×813125645³ (a number of 28 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38711 + ... + 55899.

It is an arithmetic number, because the mean of its divisors is an integer number (121988835).

Almost surely, 2^813125645 is an apocalyptic number.

It is an amenable number.

813125645 is a deficient number, since it is larger than the sum of its proper divisors (162785035).

813125645 is a wasteful number, since it uses less digits than its factorization.

813125645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26655.

The product of its digits is 28800, while the sum is 35.

The square root of 813125645 is about 28515.3580549149. The cubic root of 813125645 is about 933.3672382099.

The spelling of 813125645 in words is "eight hundred thirteen million, one hundred twenty-five thousand, six hundred forty-five".