81073899 has 8 divisors (see below), whose sum is σ = 120109520. Its totient is φ = 54049248.

The previous prime is 81073871. The next prime is 81073903. The reversal of 81073899 is 99837018.

It is not a de Polignac number, because 81073899 - 2¹² = 81069803 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (82073899) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1501342 + ... + 1501395.

It is an arithmetic number, because the mean of its divisors is an integer number (15013690).

Almost surely, 2^81073899 is an apocalyptic number.

81073899 is a deficient number, since it is larger than the sum of its proper divisors (39035621).

81073899 is a wasteful number, since it uses less digits than its factorization.

81073899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3002746 (or 3002740 counting only the distinct ones).

The product of its (nonzero) digits is 108864, while the sum is 45.

The square root of 81073899 is about 9004.1045640308. The cubic root of 81073899 is about 432.8064123330.

The spelling of 81073899 in words is "eighty-one million, seventy-three thousand, eight hundred ninety-nine".