91899559 has 4 divisors (see below), whose sum is σ = 95895216. Its totient is φ = 87903904.

The previous prime is 91899553. The next prime is 91899571. The reversal of 91899559 is 95599819.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 95599819 = 7 ⋅13657117.

It is a cyclic number.

It is not a de Polignac number, because 91899559 - 2¹¹ = 91897511 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91899553) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1997794 + ... + 1997839.

It is an arithmetic number, because the mean of its divisors is an integer number (23973804).

Almost surely, 2^91899559 is an apocalyptic number.

91899559 is a deficient number, since it is larger than the sum of its proper divisors (3995657).

91899559 is a wasteful number, since it uses less digits than its factorization.

91899559 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3995656.

The product of its digits is 1312200, while the sum is 55.

The square root of 91899559 is about 9586.4257677197. The cubic root of 91899559 is about 451.2713987341.

The spelling of 91899559 in words is "ninety-one million, eight hundred ninety-nine thousand, five hundred fifty-nine".