91989867 has 8 divisors (see below), whose sum is σ = 122698240. Its totient is φ = 61304040.

The previous prime is 91989851. The next prime is 91989869. The reversal of 91989867 is 76898919.

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

It is not a de Polignac number, because 91989867 - 2⁴ = 91989851 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91989869) 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, 10434 + ... + 17112.

It is an arithmetic number, because the mean of its divisors is an integer number (15337280).

Almost surely, 2^91989867 is an apocalyptic number.

91989867 is a deficient number, since it is larger than the sum of its proper divisors (30708373).

91989867 is a wasteful number, since it uses less digits than its factorization.

91989867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11273.

The product of its digits is 1959552, while the sum is 57.

The square root of 91989867 is about 9591.1348129405. The cubic root of 91989867 is about 451.4191690317.

The spelling of 91989867 in words is "ninety-one million, nine hundred eighty-nine thousand, eight hundred sixty-seven".