91661361 has 16 divisors (see below), whose sum is σ = 134381568. Its totient is φ = 55112400.

The previous prime is 91661347. The next prime is 91661407. The reversal of 91661361 is 16316619.

It is not a de Polignac number, because 91661361 - 2¹⁰ = 91660337 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33).

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (91661461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6745 + ... + 15126.

It is an arithmetic number, because the mean of its divisors is an integer number (8398848).

Almost surely, 2^91661361 is an apocalyptic number.

It is an amenable number.

91661361 is a deficient number, since it is larger than the sum of its proper divisors (42720207).

91661361 is a wasteful number, since it uses less digits than its factorization.

91661361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22012.

The product of its digits is 5832, while the sum is 33.

The square root of 91661361 is about 9573.9939941489. The cubic root of 91661361 is about 450.8811721628.

The spelling of 91661361 in words is "ninety-one million, six hundred sixty-one thousand, three hundred sixty-one".