816172387 has 4 divisors (see below), whose sum is σ = 831571920. Its totient is φ = 800772856.

The previous prime is 816172373. The next prime is 816172391. The reversal of 816172387 is 783271618.

816172387 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 816172387 - 2¹¹ = 816170339 is a prime.

It is a super-2 number, since 2×816172387² = 1332274730602555538, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (816172367) 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, 7699687 + ... + 7699792.

It is an arithmetic number, because the mean of its divisors is an integer number (207892980).

Almost surely, 2^816172387 is an apocalyptic number.

816172387 is a deficient number, since it is larger than the sum of its proper divisors (15399533).

816172387 is a wasteful number, since it uses less digits than its factorization.

816172387 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15399532.

The product of its digits is 112896, while the sum is 43.

The square root of 816172387 is about 28568.7309308622. The cubic root of 816172387 is about 934.5315456727.

The spelling of 816172387 in words is "eight hundred sixteen million, one hundred seventy-two thousand, three hundred eighty-seven".