290561 has 4 divisors (see below), whose sum is σ = 298452. Its totient is φ = 282672.

The previous prime is 290557. The next prime is 290593. The reversal of 290561 is 165092.

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 118336 + 172225 = 344^2 + 415^2 .

It is a cyclic number.

It is not a de Polignac number, because 290561 - 2² = 290557 is a prime.

It is an Ulam number.

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

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 290561.

It is not an unprimeable number, because it can be changed into a prime (290531) 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, 3890 + ... + 3963.

It is an arithmetic number, because the mean of its divisors is an integer number (74613).

2²⁹⁰⁵⁶¹ is an apocalyptic number.

It is an amenable number.

290561 is a deficient number, since it is larger than the sum of its proper divisors (7891).

290561 is an equidigital number, since it uses as much as digits as its factorization.

290561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7890.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 290561 is about 539.0371044743. The cubic root of 290561 is about 66.2337138085.

The spelling of 290561 in words is "two hundred ninety thousand, five hundred sixty-one".