1243240311 has 16 divisors (see below), whose sum is σ = 1764872928. Its totient is φ = 775756800.

The previous prime is 1243240309. The next prime is 1243240331. The reversal of 1243240311 is 1130423421.

It is not a de Polignac number, because 1243240311 - 2¹ = 1243240309 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1243240331) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 58110 + ... + 76571.

It is an arithmetic number, because the mean of its divisors is an integer number (110304558).

Almost surely, 2^1243240311 is an apocalyptic number.

1243240311 is a deficient number, since it is larger than the sum of its proper divisors (521632617).

1243240311 is a wasteful number, since it uses less digits than its factorization.

1243240311 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 134882.

The product of its (nonzero) digits is 576, while the sum is 21.

The square root of 1243240311 is about 35259.6130296406. The cubic root of 1243240311 is about 1075.2720597877.

Adding to 1243240311 its reverse (1130423421), we get a palindrome (2373663732).

The spelling of 1243240311 in words is "one billion, two hundred forty-three million, two hundred forty thousand, three hundred eleven".