2161111 has 4 divisors (see below), whose sum is σ = 2197800. Its totient is φ = 2124424.

The previous prime is 2161087. The next prime is 2161121. The reversal of 2161111 is 1111612.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 2161111 - 2¹¹ = 2159063 is a prime.

It is a super-3 number, since 3×2161111³ = 30279763333714231893, which contains 333 as substring.

It is a Duffinian number.

2161111 is a modest number, since divided by 1111 gives 216 as remainder.

2161111 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 2161091 and 2161100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2161121) 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 in 3 ways as a sum of consecutive naturals, for example, 18256 + ... + 18373.

It is an arithmetic number, because the mean of its divisors is an integer number (549450).

2^2161111 is an apocalyptic number.

2161111 is a deficient number, since it is larger than the sum of its proper divisors (36689).

2161111 is an equidigital number, since it uses as much as digits as its factorization.

2161111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 36688.

The product of its digits is 12, while the sum is 13.

The square root of 2161111 is about 1470.0717669556. The cubic root of 2161111 is about 129.2882403526.

Adding to 2161111 its reverse (1111612), we get a palindrome (3272723).

The spelling of 2161111 in words is "two million, one hundred sixty-one thousand, one hundred eleven".