816805194 has 8 divisors (see below), whose sum is σ = 1633610400. Its totient is φ = 272268396.

The previous prime is 816805169. The next prime is 816805237. The reversal of 816805194 is 491508618.

It is a sphenic number, since it is the product of 3 distinct primes.

816805194 is an admirable number.

It is a Smith number, since the sum of its digits (42) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Curzon number.

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, 68067094 + ... + 68067105.

It is an arithmetic number, because the mean of its divisors is an integer number (204201300).

Almost surely, 2^816805194 is an apocalyptic number.

816805194 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

816805194 is a wasteful number, since it uses less digits than its factorization.

816805194 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 136134204.

The product of its (nonzero) digits is 69120, while the sum is 42.

The square root of 816805194 is about 28579.8039531415. The cubic root of 816805194 is about 934.7730082772.

The spelling of 816805194 in words is "eight hundred sixteen million, eight hundred five thousand, one hundred ninety-four".