561091 has 2 divisors, whose sum is σ = 561092. Its totient is φ = 561090.

The previous prime is 561083. The next prime is 561097. The reversal of 561091 is 190165.

561091 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 561091 - 2³ = 561083 is a prime.

It is a super-2 number, since 2×561091² = 629646220562, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (561097) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280545 + 280546.

It is an arithmetic number, because the mean of its divisors is an integer number (280546).

2⁵⁶¹⁰⁹¹ is an apocalyptic number.

561091 is a deficient number, since it is larger than the sum of its proper divisors (1).

561091 is an equidigital number, since it uses as much as digits as its factorization.

561091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 270, while the sum is 22.

The square root of 561091 is about 749.0600776974. The cubic root of 561091 is about 82.4791989186.

The spelling of 561091 in words is "five hundred sixty-one thousand, ninety-one".