816128713 has 4 divisors (see below), whose sum is σ = 819232128. Its totient is φ = 813025300.

The previous prime is 816128693. The next prime is 816128743. The reversal of 816128713 is 317821618.

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: 317821618 = 2 ⋅158910809.

It is a cyclic number.

It is not a de Polignac number, because 816128713 - 2⁵ = 816128681 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (816128743) 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, 1551313 + ... + 1551838.

It is an arithmetic number, because the mean of its divisors is an integer number (204808032).

Almost surely, 2^816128713 is an apocalyptic number.

It is an amenable number.

816128713 is a deficient number, since it is larger than the sum of its proper divisors (3103415).

816128713 is a wasteful number, since it uses less digits than its factorization.

816128713 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3103414.

The product of its digits is 16128, while the sum is 37.

The square root of 816128713 is about 28567.9665534668. The cubic root of 816128713 is about 934.5148762127.

The spelling of 816128713 in words is "eight hundred sixteen million, one hundred twenty-eight thousand, seven hundred thirteen".