561655161 has 32 divisors (see below), whose sum is σ = 857088000. Its totient is φ = 363349584.

The previous prime is 561655139. The next prime is 561655169. The reversal of 561655161 is 161556165.

It is a de Polignac number, because none of the positive numbers 2^k-561655161 is a prime.

It is a super-3 number, since 3×561655161³ (a number of 27 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (561655169) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 123616 + ... + 128078.

It is an arithmetic number, because the mean of its divisors is an integer number (26784000).

Almost surely, 2^561655161 is an apocalyptic number.

It is an amenable number.

561655161 is a deficient number, since it is larger than the sum of its proper divisors (295432839).

561655161 is a wasteful number, since it uses less digits than its factorization.

561655161 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4610 (or 4604 counting only the distinct ones).

The product of its digits is 27000, while the sum is 36.

The square root of 561655161 is about 23699.2649886025. The cubic root of 561655161 is about 825.0683315303.

The spelling of 561655161 in words is "five hundred sixty-one million, six hundred fifty-five thousand, one hundred sixty-one".