561825261 has 16 divisors (see below), whose sum is σ = 840918400. Its totient is φ = 370687104.

The previous prime is 561825191. The next prime is 561825283. The reversal of 561825261 is 162528165.

561825261 is a `hidden beast` number, since 56 + 1 + 82 + 526 + 1 = 666.

It is not a de Polignac number, because 561825261 - 2⁷ = 561825133 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (561825361) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 104641 + ... + 109878.

It is an arithmetic number, because the mean of its divisors is an integer number (52557400).

Almost surely, 2^561825261 is an apocalyptic number.

It is an amenable number.

561825261 is a deficient number, since it is larger than the sum of its proper divisors (279093139).

561825261 is a wasteful number, since it uses less digits than its factorization.

561825261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 214625 (or 214619 counting only the distinct ones).

The product of its digits is 28800, while the sum is 36.

The square root of 561825261 is about 23702.8534358208. The cubic root of 561825261 is about 825.1516151103.

The spelling of 561825261 in words is "five hundred sixty-one million, eight hundred twenty-five thousand, two hundred sixty-one".