65561116571 has 2 divisors, whose sum is σ = 65561116572. Its totient is φ = 65561116570.

The previous prime is 65561116549. The next prime is 65561116589. The reversal of 65561116571 is 17561116556.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 65561116571 - 2⁶ = 65561116507 is a prime.

It is a super-3 number, since 3×65561116571³ (a number of 33 digits) contains 333 as substring.

It is not a weakly prime, because it can be changed into another prime (65561116541) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32780558285 + 32780558286.

It is an arithmetic number, because the mean of its divisors is an integer number (32780558286).

Almost surely, 2^65561116571 is an apocalyptic number.

65561116571 is a deficient number, since it is larger than the sum of its proper divisors (1).

65561116571 is an equidigital number, since it uses as much as digits as its factorization.

65561116571 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 189000, while the sum is 44.

The spelling of 65561116571 in words is "sixty-five billion, five hundred sixty-one million, one hundred sixteen thousand, five hundred seventy-one".