2161121 has 2 divisors, whose sum is σ = 2161122. Its totient is φ = 2161120.

The previous prime is 2161087. The next prime is 2161127. The reversal of 2161121 is 1211612.

2161121 = 1039² + 1040².

2161121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1081600 + 1079521 = 1040^2 + 1039^2 .

It is a cyclic number.

It is not a de Polignac number, because 2161121 - 2¹⁸ = 1898977 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 2161096 and 2161105.

It is not a weakly prime, because it can be changed into another prime (2161127) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1080560 + 1080561.

It is an arithmetic number, because the mean of its divisors is an integer number (1080561).

2^2161121 is an apocalyptic number.

2161121 is the 1040-th centered square number.

It is an amenable number.

2161121 is a deficient number, since it is larger than the sum of its proper divisors (1).

2161121 is an equidigital number, since it uses as much as digits as its factorization.

2161121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 24, while the sum is 14.

The square root of 2161121 is about 1470.0751681462. The cubic root of 2161121 is about 129.2884397686.

Adding to 2161121 its reverse (1211612), we get a palindrome (3372733).

The spelling of 2161121 in words is "two million, one hundred sixty-one thousand, one hundred twenty-one".