91890899 has 8 divisors (see below), whose sum is σ = 97943328. Its totient is φ = 85910400.

The previous prime is 91890893. The next prime is 91890901. The reversal of 91890899 is 99809819.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 91890899 - 2¹² = 91886803 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 91890899.

It is not an unprimeable number, because it can be changed into a prime (91890893) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15332 + ... + 20465.

It is an arithmetic number, because the mean of its divisors is an integer number (12242916).

Almost surely, 2^91890899 is an apocalyptic number.

91890899 is a deficient number, since it is larger than the sum of its proper divisors (6052429).

91890899 is a wasteful number, since it uses less digits than its factorization.

91890899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 35965.

The product of its (nonzero) digits is 419904, while the sum is 53.

The square root of 91890899 is about 9585.9740767436. The cubic root of 91890899 is about 451.2572233556.

The spelling of 91890899 in words is "ninety-one million, eight hundred ninety thousand, eight hundred ninety-nine".