1243240331 has 2 divisors, whose sum is σ = 1243240332. Its totient is φ = 1243240330.

The previous prime is 1243240309. The next prime is 1243240333. The reversal of 1243240331 is 1330423421.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 1243240331 - 2¹⁰ = 1243239307 is a prime.

It is a super-2 number, since 2×1243240331² = 3091293041249979122, which contains 22 as substring.

It is a Sophie Germain prime.

Together with 1243240333, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 1243240297 and 1243240306.

It is not a weakly prime, because it can be changed into another prime (1243240333) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621620165 + 621620166.

It is an arithmetic number, because the mean of its divisors is an integer number (621620166).

Almost surely, 2^1243240331 is an apocalyptic number.

1243240331 is a deficient number, since it is larger than the sum of its proper divisors (1).

1243240331 is an equidigital number, since it uses as much as digits as its factorization.

1243240331 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 23.

The square root of 1243240331 is about 35259.6133132512. The cubic root of 1243240331 is about 1075.2720655537.

Adding to 1243240331 its reverse (1330423421), we get a palindrome (2573663752).

The spelling of 1243240331 in words is "one billion, two hundred forty-three million, two hundred forty thousand, three hundred thirty-one".