1161105721 has 2 divisors, whose sum is σ = 1161105722. Its totient is φ = 1161105720.

The previous prime is 1161105707. The next prime is 1161105727. The reversal of 1161105721 is 1275011611.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1160083600 + 1022121 = 34060^2 + 1011^2 .

It is a cyclic number.

It is not a de Polignac number, because 1161105721 - 2¹⁷ = 1160974649 is a prime.

It is not a weakly prime, because it can be changed into another prime (1161105727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 580552860 + 580552861.

It is an arithmetic number, because the mean of its divisors is an integer number (580552861).

Almost surely, 2^1161105721 is an apocalyptic number.

It is an amenable number.

1161105721 is a deficient number, since it is larger than the sum of its proper divisors (1).

1161105721 is an equidigital number, since it uses as much as digits as its factorization.

1161105721 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 420, while the sum is 25.

The square root of 1161105721 is about 34075.0014086573. The cubic root of 1161105721 is about 1051.0513191931.

The spelling of 1161105721 in words is "one billion, one hundred sixty-one million, one hundred five thousand, seven hundred twenty-one".