813171797 has 4 divisors (see below), whose sum is σ = 813386700. Its totient is φ = 812956896.

The previous prime is 813171791. The next prime is 813171811. The reversal of 813171797 is 797171318.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 797171318 = 2 ⋅398585659.

It can be written as a sum of positive squares in 2 ways, for example, as 483604081 + 329567716 = 21991^2 + 18154^2 .

It is a cyclic number.

It is not a de Polignac number, because 813171797 - 2²² = 808977493 is a prime.

It is a super-2 number, since 2×813171797² = 1322496742872418418, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (813171791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 101672 + ... + 109377.

It is an arithmetic number, because the mean of its divisors is an integer number (203346675).

Almost surely, 2^813171797 is an apocalyptic number.

It is an amenable number.

813171797 is a deficient number, since it is larger than the sum of its proper divisors (214903).

813171797 is a wasteful number, since it uses less digits than its factorization.

813171797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214902.

The product of its digits is 74088, while the sum is 44.

The square root of 813171797 is about 28516.1672915559. The cubic root of 813171797 is about 933.3848967969.

The spelling of 813171797 in words is "eight hundred thirteen million, one hundred seventy-one thousand, seven hundred ninety-seven".