816404128 has 24 divisors (see below), whose sum is σ = 1610903700. Its totient is φ = 407285760.

The previous prime is 816404119. The next prime is 816404137. The reversal of 816404128 is 821404618.

It is an interprime number because it is at equal distance from previous prime (816404119) and next prime (816404137).

It can be written as a sum of positive squares in 2 ways, for example, as 816359184 + 44944 = 28572^2 + 212^2 .

It is a junction number, because it is equal to n+sod(n) for n = 816404093 and 816404102.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 14043 + ... + 42778.

Almost surely, 2^816404128 is an apocalyptic number.

It is an amenable number.

816404128 is a deficient number, since it is larger than the sum of its proper divisors (794499572).

816404128 is a wasteful number, since it uses less digits than its factorization.

816404128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57280 (or 57272 counting only the distinct ones).

The product of its (nonzero) digits is 12288, while the sum is 34.

The square root of 816404128 is about 28572.7864934451. The cubic root of 816404128 is about 934.6199864581.

The spelling of 816404128 in words is "eight hundred sixteen million, four hundred four thousand, one hundred twenty-eight".