243631121 has 2 divisors, whose sum is σ = 243631122. Its totient is φ = 243631120.

The previous prime is 243631109. The next prime is 243631147. The reversal of 243631121 is 121136342.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 234243025 + 9388096 = 15305^2 + 3064^2 .

It is a cyclic number.

It is not a de Polignac number, because 243631121 - 2⁶ = 243631057 is a prime.

It is a super-2 number, since 2×243631121² = 118712246239433282, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (243631151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121815560 + 121815561.

It is an arithmetic number, because the mean of its divisors is an integer number (121815561).

Almost surely, 2^243631121 is an apocalyptic number.

It is an amenable number.

243631121 is a deficient number, since it is larger than the sum of its proper divisors (1).

243631121 is an equidigital number, since it uses as much as digits as its factorization.

243631121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 864, while the sum is 23.

The square root of 243631121 is about 15608.6873567254. The cubic root of 243631121 is about 624.5649204529.

Adding to 243631121 its reverse (121136342), we get a palindrome (364767463).

The spelling of 243631121 in words is "two hundred forty-three million, six hundred thirty-one thousand, one hundred twenty-one".