90806305 has 4 divisors (see below), whose sum is σ = 108967572. Its totient is φ = 72645040.

The previous prime is 90806297. The next prime is 90806311. The reversal of 90806305 is 50360809.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 27699169 + 63107136 = 5263^2 + 7944^2 .

It is not a de Polignac number, because 90806305 - 2³ = 90806297 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9080626 + ... + 9080635.

It is an arithmetic number, because the mean of its divisors is an integer number (27241893).

Almost surely, 2^90806305 is an apocalyptic number.

It is an amenable number.

90806305 is a deficient number, since it is larger than the sum of its proper divisors (18161267).

90806305 is a wasteful number, since it uses less digits than its factorization.

90806305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18161266.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 90806305 is about 9529.2342294646. The cubic root of 90806305 is about 449.4747864170.

The spelling of 90806305 in words is "ninety million, eight hundred six thousand, three hundred five".