1131135891 has 4 divisors (see below), whose sum is σ = 1508181192. Its totient is φ = 754090592.

The previous prime is 1131135853. The next prime is 1131135893. The reversal of 1131135891 is 1985311311.

It is a happy number.

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 1131135891 - 2⁶ = 1131135827 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1131135893) 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, 188522646 + ... + 188522651.

It is an arithmetic number, because the mean of its divisors is an integer number (377045298).

Almost surely, 2^1131135891 is an apocalyptic number.

1131135891 is a deficient number, since it is larger than the sum of its proper divisors (377045301).

1131135891 is an equidigital number, since it uses as much as digits as its factorization.

1131135891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 377045300.

The product of its digits is 3240, while the sum is 33.

The square root of 1131135891 is about 33632.3637438703. The cubic root of 1131135891 is about 1041.9293239248.

The spelling of 1131135891 in words is "one billion, one hundred thirty-one million, one hundred thirty-five thousand, eight hundred ninety-one".