90985809 has 8 divisors (see below), whose sum is σ = 121586400. Its totient is φ = 60521216.

The previous prime is 90985781. The next prime is 90985841. The reversal of 90985809 is 90858909.

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 90985809 - 2⁷ = 90985681 is a prime.

It is not an unprimeable number, because it can be changed into a prime (90935809) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 32427 + ... + 35120.

It is an arithmetic number, because the mean of its divisors is an integer number (15198300).

Almost surely, 2^90985809 is an apocalyptic number.

It is an amenable number.

90985809 is a deficient number, since it is larger than the sum of its proper divisors (30600591).

90985809 is a wasteful number, since it uses less digits than its factorization.

90985809 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 67999.

The product of its (nonzero) digits is 233280, while the sum is 48.

The square root of 90985809 is about 9538.6481746629. The cubic root of 90985809 is about 449.7707622545.

The spelling of 90985809 in words is "ninety million, nine hundred eighty-five thousand, eight hundred nine".