816715231 has 4 divisors (see below), whose sum is σ = 818277352. Its totient is φ = 815153112.

The previous prime is 816715223. The next prime is 816715267. The reversal of 816715231 is 132517618.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 816715231 - 2³ = 816715223 is a prime.

It is a super-2 number, since 2×816715231² = 1334047537094766722, 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 (816715831) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 780276 + ... + 781321.

It is an arithmetic number, because the mean of its divisors is an integer number (204569338).

Almost surely, 2^816715231 is an apocalyptic number.

816715231 is a deficient number, since it is larger than the sum of its proper divisors (1562121).

816715231 is a wasteful number, since it uses less digits than its factorization.

816715231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1562120.

The product of its digits is 10080, while the sum is 34.

The square root of 816715231 is about 28578.2300186698. The cubic root of 816715231 is about 934.7386883552.

The spelling of 816715231 in words is "eight hundred sixteen million, seven hundred fifteen thousand, two hundred thirty-one".