7111655561 has 2 divisors, whose sum is σ = 7111655562. Its totient is φ = 7111655560.

The previous prime is 7111655503. The next prime is 7111655567. The reversal of 7111655561 is 1655561117.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6952391161 + 159264400 = 83381^2 + 12620^2 .

It is a cyclic number.

It is not a de Polignac number, because 7111655561 - 2¹⁸ = 7111393417 is a prime.

It is not a weakly prime, because it can be changed into another prime (7111655567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3555827780 + 3555827781.

It is an arithmetic number, because the mean of its divisors is an integer number (3555827781).

Almost surely, 2^7111655561 is an apocalyptic number.

It is an amenable number.

7111655561 is a deficient number, since it is larger than the sum of its proper divisors (1).

7111655561 is an equidigital number, since it uses as much as digits as its factorization.

7111655561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 31500, while the sum is 38.

The square root of 7111655561 is about 84330.6324000953. The cubic root of 7111655561 is about 1923.0485028627.

The spelling of 7111655561 in words is "seven billion, one hundred eleven million, six hundred fifty-five thousand, five hundred sixty-one".