2121181 has 2 divisors, whose sum is σ = 2121182. Its totient is φ = 2121180.

The previous prime is 2121167. The next prime is 2121187. The reversal of 2121181 is 1811212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1836025 + 285156 = 1355^2 + 534^2 .

It is a cyclic number.

It is not a de Polignac number, because 2121181 - 2¹³ = 2112989 is a prime.

It is a super-2 number, since 2×2121181² = 8998817669522, which contains 22 as substring.

2121181 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2121187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060590 + 1060591.

It is an arithmetic number, because the mean of its divisors is an integer number (1060591).

2^2121181 is an apocalyptic number.

It is an amenable number.

2121181 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121181 is an equidigital number, since it uses as much as digits as its factorization.

2121181 is an evil number, because the sum of its binary digits is even.

The product of its digits is 32, while the sum is 16.

The square root of 2121181 is about 1456.4274784554. The cubic root of 2121181 is about 128.4870159026.

Adding to 2121181 its reverse (1811212), we get a palindrome (3932393).

The spelling of 2121181 in words is "two million, one hundred twenty-one thousand, one hundred eighty-one".