1311121241 has 4 divisors (see below), whose sum is σ = 1312684800. Its totient is φ = 1309557684.

The previous prime is 1311121153. The next prime is 1311121249. The reversal of 1311121241 is 1421211131.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1311121241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1311121249) 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, 780521 + ... + 782198.

It is an arithmetic number, because the mean of its divisors is an integer number (328171200).

Almost surely, 2^1311121241 is an apocalyptic number.

It is an amenable number.

1311121241 is a deficient number, since it is larger than the sum of its proper divisors (1563559).

1311121241 is an equidigital number, since it uses as much as digits as its factorization.

1311121241 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1563558.

The product of its digits is 48, while the sum is 17.

The square root of 1311121241 is about 36209.4081835094. The cubic root of 1311121241 is about 1094.4962664296.

Adding to 1311121241 its reverse (1421211131), we get a palindrome (2732332372).

The spelling of 1311121241 in words is "one billion, three hundred eleven million, one hundred twenty-one thousand, two hundred forty-one".