91099161 has 10 divisors (see below), whose sum is σ = 136086522. Its totient is φ = 60732720.

The previous prime is 91099157. The next prime is 91099181. The reversal of 91099161 is 16199019.

It can be written as a sum of positive squares in only one way, i.e., 71571600 + 19527561 = 8460^2 + 4419^2 .

It is not a de Polignac number, because 91099161 - 2² = 91099157 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91099181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 9 ways as a sum of consecutive naturals, for example, 562260 + ... + 562421.

Almost surely, 2^91099161 is an apocalyptic number.

It is an amenable number.

91099161 is a deficient number, since it is larger than the sum of its proper divisors (44987361).

91099161 is a wasteful number, since it uses less digits than its factorization.

91099161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1124693 (or 1124684 counting only the distinct ones).

The product of its (nonzero) digits is 4374, while the sum is 36.

The square root of 91099161 is about 9544.5880476844. The cubic root of 91099161 is about 449.9574626458.

The spelling of 91099161 in words is "ninety-one million, ninety-nine thousand, one hundred sixty-one".