813257656865 has 8 divisors (see below), whose sum is σ = 976036920768. Its totient is φ = 650520970480.

The previous prime is 813257656817. The next prime is 813257656867. The reversal of 813257656865 is 568656752318.

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

It is a de Polignac number, because none of the positive numbers 2^k-813257656865 is a prime.

It is a super-2 number, since 2×813257656865² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 813257656798 and 813257656807.

It is not an unprimeable number, because it can be changed into a prime (813257656867) 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, 10602341 + ... + 10678770.

It is an arithmetic number, because the mean of its divisors is an integer number (122004615096).

Almost surely, 2^813257656865 is an apocalyptic number.

It is an amenable number.

813257656865 is a deficient number, since it is larger than the sum of its proper divisors (162779263903).

813257656865 is a wasteful number, since it uses less digits than its factorization.

813257656865 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21288759.

The product of its digits is 72576000, while the sum is 62.

The spelling of 813257656865 in words is "eight hundred thirteen billion, two hundred fifty-seven million, six hundred fifty-six thousand, eight hundred sixty-five".