611120561 has 2 divisors, whose sum is σ = 611120562. Its totient is φ = 611120560.

The previous prime is 611120551. The next prime is 611120563. The reversal of 611120561 is 165021116.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 544942336 + 66178225 = 23344^2 + 8135^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-611120561 is a prime.

Together with 611120563, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (611120563) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 305560280 + 305560281.

It is an arithmetic number, because the mean of its divisors is an integer number (305560281).

Almost surely, 2^611120561 is an apocalyptic number.

It is an amenable number.

611120561 is a deficient number, since it is larger than the sum of its proper divisors (1).

611120561 is an equidigital number, since it uses as much as digits as its factorization.

611120561 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 360, while the sum is 23.

The square root of 611120561 is about 24720.8527563270. The cubic root of 611120561 is about 848.6116023871.

Adding to 611120561 its reverse (165021116), we get a palindrome (776141677).

The spelling of 611120561 in words is "six hundred eleven million, one hundred twenty thousand, five hundred sixty-one".