91085489 has 4 divisors (see below), whose sum is σ = 99366000. Its totient is φ = 82804980.

The previous prime is 91085461. The next prime is 91085503. The reversal of 91085489 is 98458019.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 91085489 - 2⁸ = 91085233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91085689) 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, 4140239 + ... + 4140260.

It is an arithmetic number, because the mean of its divisors is an integer number (24841500).

Almost surely, 2^91085489 is an apocalyptic number.

It is an amenable number.

91085489 is a deficient number, since it is larger than the sum of its proper divisors (8280511).

91085489 is a wasteful number, since it uses less digits than its factorization.

91085489 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8280510.

The product of its (nonzero) digits is 103680, while the sum is 44.

The square root of 91085489 is about 9543.8718034140. The cubic root of 91085489 is about 449.9349519145.

The spelling of 91085489 in words is "ninety-one million, eighty-five thousand, four hundred eighty-nine".