90305 has 4 divisors (see below), whose sum is σ = 108372. Its totient is φ = 72240.

The previous prime is 90289. The next prime is 90313. The reversal of 90305 is 50309.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50309 = 7 ⋅7187.

It can be written as a sum of positive squares in 2 ways, for example, as 53824 + 36481 = 232^2 + 191^2 .

It is not a de Polignac number, because 90305 - 2⁴ = 90289 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is a Duffinian number.

It is a plaindrome in base 9.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9026 + ... + 9035.

It is an arithmetic number, because the mean of its divisors is an integer number (27093).

2⁹⁰³⁰⁵ is an apocalyptic number.

It is an amenable number.

90305 is a deficient number, since it is larger than the sum of its proper divisors (18067).

90305 is a wasteful number, since it uses less digits than its factorization.

90305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18066.

The product of its (nonzero) digits is 135, while the sum is 17.

The square root of 90305 is about 300.5079033902. The cubic root of 90305 is about 44.8646136633.

It can be divided in two parts, 9030 and 5, that multiplied together give a triangular number (45150 = T₃₀₀).

The spelling of 90305 in words is "ninety thousand, three hundred five".