816505135 has 16 divisors (see below), whose sum is σ = 993189600. Its totient is φ = 644317696.

The previous prime is 816505133. The next prime is 816505139. The reversal of 816505135 is 531505618.

816505135 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 816505135 - 2¹ = 816505133 is a prime.

It is a super-4 number, since 4×816505135⁴ (a number of 37 digits) contains 4444 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 816505135.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816505133) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 205851 + ... + 209779.

It is an arithmetic number, because the mean of its divisors is an integer number (62074350).

Almost surely, 2^816505135 is an apocalyptic number.

816505135 is a deficient number, since it is larger than the sum of its proper divisors (176684465).

816505135 is a wasteful number, since it uses less digits than its factorization.

816505135 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4490.

The product of its (nonzero) digits is 18000, while the sum is 34.

The square root of 816505135 is about 28574.5539772715. The cubic root of 816505135 is about 934.6585291621.

The spelling of 816505135 in words is "eight hundred sixteen million, five hundred five thousand, one hundred thirty-five".