91157089 has 2 divisors, whose sum is σ = 91157090. Its totient is φ = 91157088.

The previous prime is 91157057. The next prime is 91157107. The reversal of 91157089 is 98075119.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 54760000 + 36397089 = 7400^2 + 6033^2 .

It is an emirp because it is prime and its reverse (98075119) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91157089 - 2⁵ = 91157057 is a prime.

It is a super-2 number, since 2×91157089² = 16619229749907842, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (91157029) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45578544 + 45578545.

It is an arithmetic number, because the mean of its divisors is an integer number (45578545).

Almost surely, 2^91157089 is an apocalyptic number.

It is an amenable number.

91157089 is a deficient number, since it is larger than the sum of its proper divisors (1).

91157089 is an equidigital number, since it uses as much as digits as its factorization.

91157089 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 22680, while the sum is 40.

The square root of 91157089 is about 9547.6221647068. The cubic root of 91157089 is about 450.0528152002.

The spelling of 91157089 in words is "ninety-one million, one hundred fifty-seven thousand, eighty-nine".