243320431 has 2 divisors, whose sum is σ = 243320432. Its totient is φ = 243320430.

The previous prime is 243320387. The next prime is 243320449. The reversal of 243320431 is 134023342.

It is a happy number.

243320431 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 243320431 - 2⁹ = 243319919 is a prime.

It is a super-2 number, since 2×243320431² = 118409664284051522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243320131) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121660215 + 121660216.

It is an arithmetic number, because the mean of its divisors is an integer number (121660216).

Almost surely, 2^243320431 is an apocalyptic number.

243320431 is a deficient number, since it is larger than the sum of its proper divisors (1).

243320431 is an equidigital number, since it uses as much as digits as its factorization.

243320431 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1728, while the sum is 22.

The square root of 243320431 is about 15598.7317112642. The cubic root of 243320431 is about 624.2993158804.

Adding to 243320431 its reverse (134023342), we get a palindrome (377343773).

The spelling of 243320431 in words is "two hundred forty-three million, three hundred twenty thousand, four hundred thirty-one".