816506128 has 20 divisors (see below), whose sum is σ = 1611830988. Its totient is φ = 400549760.

The previous prime is 816506123. The next prime is 816506161. The reversal of 816506128 is 821605618.

It can be written as a sum of positive squares in 2 ways, for example, as 556393744 + 260112384 = 23588^2 + 16128^2 .

It is not an unprimeable number, because it can be changed into a prime (816506123) 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, 480583 + ... + 482278.

Almost surely, 2^816506128 is an apocalyptic number.

It is an amenable number.

816506128 is a deficient number, since it is larger than the sum of its proper divisors (795324860).

816506128 is a wasteful number, since it uses less digits than its factorization.

816506128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 962922 (or 962916 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 37.

The square root of 816506128 is about 28574.5713528655. The cubic root of 816506128 is about 934.6589080597.

It can be divided in two parts, 81650 and 6128, that added together give a palindrome (87778).

The spelling of 816506128 in words is "eight hundred sixteen million, five hundred six thousand, one hundred twenty-eight".