81199294 has 16 divisors (see below), whose sum is σ = 133436160. Its totient is φ = 36751960.

The previous prime is 81199289. The next prime is 81199297. The reversal of 81199294 is 49299118.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 81199294.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81199297) 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 7 ways as a sum of consecutive naturals, for example, 2464 + ... + 12979.

It is an arithmetic number, because the mean of its divisors is an integer number (8339760).

Almost surely, 2^81199294 is an apocalyptic number.

81199294 is a deficient number, since it is larger than the sum of its proper divisors (52236866).

81199294 is a wasteful number, since it uses less digits than its factorization.

81199294 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15695.

The product of its digits is 46656, while the sum is 43.

The square root of 81199294 is about 9011.0650868807. The cubic root of 81199294 is about 433.0294343927.

The spelling of 81199294 in words is "eighty-one million, one hundred ninety-nine thousand, two hundred ninety-four".