81107793 has 24 divisors (see below), whose sum is σ = 126584640. Its totient is φ = 49747680.

The previous prime is 81107783. The next prime is 81107797. The reversal of 81107793 is 39770118.

It is not a de Polignac number, because 81107793 - 2⁴ = 81107777 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81107797) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 41038 + ... + 42968.

It is an arithmetic number, because the mean of its divisors is an integer number (5274360).

Almost surely, 2^81107793 is an apocalyptic number.

It is an amenable number.

81107793 is a deficient number, since it is larger than the sum of its proper divisors (45476847).

81107793 is a wasteful number, since it uses less digits than its factorization.

81107793 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2309 (or 2306 counting only the distinct ones).

The product of its (nonzero) digits is 10584, while the sum is 36.

The square root of 81107793 is about 9005.9865089839. The cubic root of 81107793 is about 432.8667173836.

The spelling of 81107793 in words is "eighty-one million, one hundred seven thousand, seven hundred ninety-three".