561655543 has 2 divisors, whose sum is σ = 561655544. Its totient is φ = 561655542.

The previous prime is 561655517. The next prime is 561655559. The reversal of 561655543 is 345556165.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-561655543 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 561655496 and 561655505.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (561655513) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 280827771 + 280827772.

It is an arithmetic number, because the mean of its divisors is an integer number (280827772).

Almost surely, 2^561655543 is an apocalyptic number.

561655543 is a deficient number, since it is larger than the sum of its proper divisors (1).

561655543 is an equidigital number, since it uses as much as digits as its factorization.

561655543 is an evil number, because the sum of its binary digits is even.

The product of its digits is 270000, while the sum is 40.

The square root of 561655543 is about 23699.2730479228. The cubic root of 561655543 is about 825.0685185822.

The spelling of 561655543 in words is "five hundred sixty-one million, six hundred fifty-five thousand, five hundred forty-three".