243121201231 has 4 divisors (see below), whose sum is σ = 244669744072. Its totient is φ = 241572658392.

The previous prime is 243121201229. The next prime is 243121201247. The reversal of 243121201231 is 132102121342.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 132102121342 = 2 ⋅66051060671.

It is a cyclic number.

It is not a de Polignac number, because 243121201231 - 2¹ = 243121201229 is a prime.

It is a super-2 number, since 2×243121201231² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243121201291) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 774271185 + ... + 774271498.

It is an arithmetic number, because the mean of its divisors is an integer number (61167436018).

Almost surely, 2^243121201231 is an apocalyptic number.

243121201231 is a deficient number, since it is larger than the sum of its proper divisors (1548542841).

243121201231 is a wasteful number, since it uses less digits than its factorization.

243121201231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1548542840.

The product of its (nonzero) digits is 576, while the sum is 22.

Adding to 243121201231 its reverse (132102121342), we get a palindrome (375223322573).

The spelling of 243121201231 in words is "two hundred forty-three billion, one hundred twenty-one million, two hundred one thousand, two hundred thirty-one".