91689605 has 16 divisors (see below), whose sum is σ = 125971200. Its totient is φ = 62760192.

The previous prime is 91689583. The next prime is 91689623. The reversal of 91689605 is 50698619.

It is a cyclic number.

It is not a de Polignac number, because 91689605 - 2¹⁰ = 91688581 is a prime.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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, 20621 + ... + 24669.

It is an arithmetic number, because the mean of its divisors is an integer number (7873200).

Almost surely, 2^91689605 is an apocalyptic number.

It is an amenable number.

91689605 is a deficient number, since it is larger than the sum of its proper divisors (34281595).

91689605 is a wasteful number, since it uses less digits than its factorization.

91689605 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4708.

The product of its (nonzero) digits is 116640, while the sum is 44.

The square root of 91689605 is about 9575.4689180217. The cubic root of 91689605 is about 450.9274780432.

The spelling of 91689605 in words is "ninety-one million, six hundred eighty-nine thousand, six hundred five".