816984909 has 48 divisors (see below), whose sum is σ = 1332834048. Its totient is φ = 478469376.

The previous prime is 816984893. The next prime is 816984913. The reversal of 816984909 is 909489618.

It is not a de Polignac number, because 816984909 - 2⁴ = 816984893 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816984989) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 626352 + ... + 627654.

It is an arithmetic number, because the mean of its divisors is an integer number (27767376).

Almost surely, 2^816984909 is an apocalyptic number.

It is an amenable number.

816984909 is a deficient number, since it is larger than the sum of its proper divisors (515849139).

816984909 is a wasteful number, since it uses less digits than its factorization.

816984909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1578 (or 1575 counting only the distinct ones).

The product of its (nonzero) digits is 1119744, while the sum is 54.

The square root of 816984909 is about 28582.9478710647. The cubic root of 816984909 is about 934.8415600825.

The spelling of 816984909 in words is "eight hundred sixteen million, nine hundred eighty-four thousand, nine hundred nine".