243211121 has 2 divisors, whose sum is σ = 243211122. Its totient is φ = 243211120.

The previous prime is 243211109. The next prime is 243211127. The reversal of 243211121 is 121112342.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 242736400 + 474721 = 15580^2 + 689^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-243211121 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 243211121.

It is not a weakly prime, because it can be changed into another prime (243211127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121605560 + 121605561.

It is an arithmetic number, because the mean of its divisors is an integer number (121605561).

Almost surely, 2^243211121 is an apocalyptic number.

It is an amenable number.

243211121 is a deficient number, since it is larger than the sum of its proper divisors (1).

243211121 is an equidigital number, since it uses as much as digits as its factorization.

243211121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96, while the sum is 17.

The square root of 243211121 is about 15595.2275071574. The cubic root of 243211121 is about 624.2058145118.

Adding to 243211121 its reverse (121112342), we get a palindrome (364323463).

The spelling of 243211121 in words is "two hundred forty-three million, two hundred eleven thousand, one hundred twenty-one".