243249431 has 2 divisors, whose sum is σ = 243249432. Its totient is φ = 243249430.

The previous prime is 243249397. The next prime is 243249439. The reversal of 243249431 is 134942342.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 243249431 - 2⁶ = 243249367 is a prime.

It is a super-2 number, since 2×243249431² = 118340571363647522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (243249439) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 121624715 + 121624716.

It is an arithmetic number, because the mean of its divisors is an integer number (121624716).

Almost surely, 2^243249431 is an apocalyptic number.

243249431 is a deficient number, since it is larger than the sum of its proper divisors (1).

243249431 is an equidigital number, since it uses as much as digits as its factorization.

243249431 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20736, while the sum is 32.

The square root of 243249431 is about 15596.4557191690. The cubic root of 243249431 is about 624.2385872310.

The spelling of 243249431 in words is "two hundred forty-three million, two hundred forty-nine thousand, four hundred thirty-one".