81836199 has 6 divisors (see below), whose sum is σ = 118207856. Its totient is φ = 54557460.

The previous prime is 81836177. The next prime is 81836201. The reversal of 81836199 is 99163818.

It is not a de Polignac number, because 81836199 - 2⁹ = 81835687 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81836099) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 4546447 + ... + 4546464.

Almost surely, 2^81836199 is an apocalyptic number.

81836199 is a deficient number, since it is larger than the sum of its proper divisors (36371657).

81836199 is a wasteful number, since it uses less digits than its factorization.

81836199 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9092917 (or 9092914 counting only the distinct ones).

The product of its digits is 93312, while the sum is 45.

The square root of 81836199 is about 9046.3362197080. The cubic root of 81836199 is about 434.1586750878.

The spelling of 81836199 in words is "eighty-one million, eight hundred thirty-six thousand, one hundred ninety-nine".