290506 has 4 divisors (see below), whose sum is σ = 435762. Its totient is φ = 145252.

The previous prime is 290497. The next prime is 290509. The reversal of 290506 is 605092.

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

It can be written as a sum of positive squares in only one way, i.e., 265225 + 25281 = 515^2 + 159^2 .

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (290509) by changing a digit.

290506 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 as a sum of consecutive naturals, namely, 72625 + ... + 72628.

2²⁹⁰⁵⁰⁶ is an apocalyptic number.

290506 is a deficient number, since it is larger than the sum of its proper divisors (145256).

290506 is a wasteful number, since it uses less digits than its factorization.

290506 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 145255.

The product of its (nonzero) digits is 540, while the sum is 22.

The square root of 290506 is about 538.9860851636. The cubic root of 290506 is about 66.2295344404.

Adding to 290506 its reverse (605092), we get a palindrome (895598).

The spelling of 290506 in words is "two hundred ninety thousand, five hundred six".