1131243011 has 4 divisors (see below), whose sum is σ = 1157551032. Its totient is φ = 1104934992.

The previous prime is 1131242989. The next prime is 1131243023. The reversal of 1131243011 is 1103421311.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1131243011 - 2²⁶ = 1064134147 is a prime.

It is a super-2 number, since 2×1131243011² = 2559421499872692242, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1131243511) 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, 13153946 + ... + 13154031.

It is an arithmetic number, because the mean of its divisors is an integer number (289387758).

Almost surely, 2^1131243011 is an apocalyptic number.

1131243011 is a deficient number, since it is larger than the sum of its proper divisors (26308021).

1131243011 is an equidigital number, since it uses as much as digits as its factorization.

1131243011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26308020.

The product of its (nonzero) digits is 72, while the sum is 17.

The square root of 1131243011 is about 33633.9562198680. The cubic root of 1131243011 is about 1041.9622135617.

Adding to 1131243011 its reverse (1103421311), we get a palindrome (2234664322).

The spelling of 1131243011 in words is "one billion, one hundred thirty-one million, two hundred forty-three thousand, eleven".