81199194 has 8 divisors (see below), whose sum is σ = 162398400. Its totient is φ = 27066396.

The previous prime is 81199187. The next prime is 81199207. The reversal of 81199194 is 49199118.

It is a happy number.

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

81199194 is an admirable number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6766594 + ... + 6766605.

It is an arithmetic number, because the mean of its divisors is an integer number (20299800).

Almost surely, 2^81199194 is an apocalyptic number.

81199194 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.

81199194 is a wasteful number, since it uses less digits than its factorization.

81199194 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13533204.

The product of its digits is 23328, while the sum is 42.

The square root of 81199194 is about 9011.0595381453. The cubic root of 81199194 is about 433.0292566286.

The spelling of 81199194 in words is "eighty-one million, one hundred ninety-nine thousand, one hundred ninety-four".