1116721121 has 2 divisors, whose sum is σ = 1116721122. Its totient is φ = 1116721120.

The previous prime is 1116721069. The next prime is 1116721129. The reversal of 1116721121 is 1211276111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 820020496 + 296700625 = 28636^2 + 17225^2 .

It is a cyclic number.

It is not a de Polignac number, because 1116721121 - 2¹⁸ = 1116458977 is a prime.

It is not a weakly prime, because it can be changed into another prime (1116721129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 558360560 + 558360561.

It is an arithmetic number, because the mean of its divisors is an integer number (558360561).

Almost surely, 2^1116721121 is an apocalyptic number.

It is an amenable number.

1116721121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1116721121 is an equidigital number, since it uses as much as digits as its factorization.

1116721121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 168, while the sum is 23.

The square root of 1116721121 is about 33417.3775302611. The cubic root of 1116721121 is about 1037.4844036171.

Adding to 1116721121 its reverse (1211276111), we get a palindrome (2327997232).

The spelling of 1116721121 in words is "one billion, one hundred sixteen million, seven hundred twenty-one thousand, one hundred twenty-one".