305890 has 24 divisors (see below), whose sum is σ = 599508. Its totient is φ = 112320.

The previous prime is 305873. The next prime is 305917. The reversal of 305890 is 98503.

It can be written as a sum of positive squares in 6 ways, for example, as 81 + 305809 = 9^2 + 553^2 .

It is a Smith number, since the sum of its digits (25) coincides with the sum of the digits of its prime factors.

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

It is a nialpdrome in base 13.

It is an unprimeable number.

305890 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1600 + ... + 1780.

2³⁰⁵⁸⁹⁰ is an apocalyptic number.

305890 is a deficient number, since it is larger than the sum of its proper divisors (293618).

305890 is a wasteful number, since it uses less digits than its factorization.

305890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214 (or 201 counting only the distinct ones).

The product of its (nonzero) digits is 1080, while the sum is 25.

The square root of 305890 is about 553.0732320407. The cubic root of 305890 is about 67.3785653883.

The spelling of 305890 in words is "three hundred five thousand, eight hundred ninety".