81112783 has 4 divisors (see below), whose sum is σ = 81133920. Its totient is φ = 81091648.

The previous prime is 81112753. The next prime is 81112799. The reversal of 81112783 is 38721118.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 38721118 = 2 ⋅19360559.

It is a cyclic number.

It is not a de Polignac number, because 81112783 - 2⁵ = 81112751 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 (81112753) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3010 + ... + 13087.

It is an arithmetic number, because the mean of its divisors is an integer number (20283480).

Almost surely, 2^81112783 is an apocalyptic number.

81112783 is a deficient number, since it is larger than the sum of its proper divisors (21137).

81112783 is a wasteful number, since it uses less digits than its factorization.

81112783 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21136.

The product of its digits is 2688, while the sum is 31.

The square root of 81112783 is about 9006.2635426685. The cubic root of 81112783 is about 432.8755942972.

The spelling of 81112783 in words is "eighty-one million, one hundred twelve thousand, seven hundred eighty-three".