91681111 has 2 divisors, whose sum is σ = 91681112. Its totient is φ = 91681110.

The previous prime is 91681097. The next prime is 91681141. The reversal of 91681111 is 11118619.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-91681111 is a prime.

It is a super-2 number, since 2×91681111² = 16810852228388642, which contains 22 as substring.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 91681111.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91681141) 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 as a sum of consecutive naturals, namely, 45840555 + 45840556.

It is an arithmetic number, because the mean of its divisors is an integer number (45840556).

Almost surely, 2^91681111 is an apocalyptic number.

91681111 is a deficient number, since it is larger than the sum of its proper divisors (1).

91681111 is an equidigital number, since it uses as much as digits as its factorization.

91681111 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 432, while the sum is 28.

The square root of 91681111 is about 9575.0253785564. The cubic root of 91681111 is about 450.9135531776.

The spelling of 91681111 in words is "ninety-one million, six hundred eighty-one thousand, one hundred eleven".