91158917 has 2 divisors, whose sum is σ = 91158918. Its totient is φ = 91158916.

The previous prime is 91158911. The next prime is 91158923. The reversal of 91158917 is 71985119.

It is a balanced prime because it is at equal distance from previous prime (91158911) and next prime (91158923).

It can be written as a sum of positive squares in only one way, i.e., 68128516 + 23030401 = 8254^2 + 4799^2 .

It is a cyclic number.

It is not a de Polignac number, because 91158917 - 2⁴ = 91158901 is a prime.

It is a super-2 number, since 2×91158917² = 16619896297225778, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91158911) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45579458 + 45579459.

It is an arithmetic number, because the mean of its divisors is an integer number (45579459).

Almost surely, 2^91158917 is an apocalyptic number.

It is an amenable number.

91158917 is a deficient number, since it is larger than the sum of its proper divisors (1).

91158917 is an equidigital number, since it uses as much as digits as its factorization.

91158917 is an evil number, because the sum of its binary digits is even.

The product of its digits is 22680, while the sum is 41.

The square root of 91158917 is about 9547.7178948689. The cubic root of 91158917 is about 450.0558235274.

The spelling of 91158917 in words is "ninety-one million, one hundred fifty-eight thousand, nine hundred seventeen".