90505289 has 4 divisors (see below), whose sum is σ = 103434624. Its totient is φ = 77575956.

The previous prime is 90505279. The next prime is 90505301. The reversal of 90505289 is 98250509.

It is a happy number.

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 a de Polignac number, because none of the positive numbers 2^k-90505289 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (90505279) 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, 6464657 + ... + 6464670.

It is an arithmetic number, because the mean of its divisors is an integer number (25858656).

Almost surely, 2^90505289 is an apocalyptic number.

It is an amenable number.

90505289 is a deficient number, since it is larger than the sum of its proper divisors (12929335).

90505289 is a wasteful number, since it uses less digits than its factorization.

90505289 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12929334.

The product of its (nonzero) digits is 32400, while the sum is 38.

The square root of 90505289 is about 9513.4267748272. The cubic root of 90505289 is about 448.9775783566.

The spelling of 90505289 in words is "ninety million, five hundred five thousand, two hundred eighty-nine".