81116567 has 16 divisors (see below), whose sum is σ = 100953600. Its totient is φ = 63594720.

The previous prime is 81116557. The next prime is 81116587. The reversal of 81116567 is 76561118.

It is not a de Polignac number, because 81116567 - 2²⁶ = 14007703 is a prime.

It is a Smith number, since the sum of its digits (35) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81116507) 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 15 ways as a sum of consecutive naturals, for example, 6659 + ... + 14372.

It is an arithmetic number, because the mean of its divisors is an integer number (6309600).

Almost surely, 2^81116567 is an apocalyptic number.

81116567 is a deficient number, since it is larger than the sum of its proper divisors (19837033).

81116567 is a wasteful number, since it uses less digits than its factorization.

81116567 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21086.

The product of its digits is 10080, while the sum is 35.

The square root of 81116567 is about 9006.4736162385. The cubic root of 81116567 is about 432.8823255658.

The spelling of 81116567 in words is "eighty-one million, one hundred sixteen thousand, five hundred sixty-seven".