816317381 has 4 divisors (see below), whose sum is σ = 890528064. Its totient is φ = 742106700.

The previous prime is 816317363. The next prime is 816317399. The reversal of 816317381 is 183713618.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (816317363) and next prime (816317399).

It is a cyclic number.

It is not a de Polignac number, because 816317381 - 2¹⁸ = 816055237 is a prime.

It is a super-2 number, since 2×816317381² = 1332748133045398322, 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 (816317321) 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, 37105325 + ... + 37105346.

It is an arithmetic number, because the mean of its divisors is an integer number (222632016).

Almost surely, 2^816317381 is an apocalyptic number.

It is an amenable number.

816317381 is a deficient number, since it is larger than the sum of its proper divisors (74210683).

816317381 is a wasteful number, since it uses less digits than its factorization.

816317381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 74210682.

The product of its digits is 24192, while the sum is 38.

The square root of 816317381 is about 28571.2684527656. The cubic root of 816317381 is about 934.5868826112.

The spelling of 816317381 in words is "eight hundred sixteen million, three hundred seventeen thousand, three hundred eighty-one".