290128561 has 4 divisors (see below), whose sum is σ = 290188800. Its totient is φ = 290068324.

The previous prime is 290128529. The next prime is 290128583. The reversal of 290128561 is 165821092.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 290128561 - 2⁵ = 290128529 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (290129561) by changing a digit.

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, 22201 + ... + 32758.

It is an arithmetic number, because the mean of its divisors is an integer number (72547200).

Almost surely, 2^290128561 is an apocalyptic number.

It is an amenable number.

290128561 is a deficient number, since it is larger than the sum of its proper divisors (60239).

290128561 is an equidigital number, since it uses as much as digits as its factorization.

290128561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 60238.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 290128561 is about 17033.1606286091. The cubic root of 290128561 is about 662.0083917180.

It can be divided in two parts, 29012 and 8561, that added together give a palindrome (37573).

The spelling of 290128561 in words is "two hundred ninety million, one hundred twenty-eight thousand, five hundred sixty-one".