243505312231 has 4 divisors (see below), whose sum is σ = 243518005432. Its totient is φ = 243492619032.

The previous prime is 243505312229. The next prime is 243505312301. The reversal of 243505312231 is 132213505342.

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 243505312231 - 2¹ = 243505312229 is a prime.

It is a super-2 number, since 2×243505312231² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 243505312193 and 243505312202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (243505312031) 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, 6317781 + ... + 6356206.

It is an arithmetic number, because the mean of its divisors is an integer number (60879501358).

Almost surely, 2^243505312231 is an apocalyptic number.

243505312231 is a deficient number, since it is larger than the sum of its proper divisors (12693201).

243505312231 is a wasteful number, since it uses less digits than its factorization.

243505312231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12693200.

The product of its (nonzero) digits is 21600, while the sum is 31.

Adding to 243505312231 its reverse (132213505342), we get a palindrome (375718817573).

The spelling of 243505312231 in words is "two hundred forty-three billion, five hundred five million, three hundred twelve thousand, two hundred thirty-one".