816595997 has 4 divisors (see below), whose sum is σ = 933252576. Its totient is φ = 699939420.

The previous prime is 816595993. The next prime is 816596023. The reversal of 816595997 is 799595618.

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, and also an emirpimes, since its reverse is a distinct semiprime: 799595618 = 2 ⋅399797809.

It is a cyclic number.

It is not a de Polignac number, because 816595997 - 2² = 816595993 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816595993) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 58328279 + ... + 58328292.

It is an arithmetic number, because the mean of its divisors is an integer number (233313144).

Almost surely, 2^816595997 is an apocalyptic number.

It is an amenable number.

816595997 is a deficient number, since it is larger than the sum of its proper divisors (116656579).

816595997 is a wasteful number, since it uses less digits than its factorization.

816595997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116656578.

The product of its digits is 6123600, while the sum is 59.

The square root of 816595997 is about 28576.1438441228. The cubic root of 816595997 is about 934.6931979758.

The spelling of 816595997 in words is "eight hundred sixteen million, five hundred ninety-five thousand, nine hundred ninety-seven".