1131305431 has 4 divisors (see below), whose sum is σ = 1131733872. Its totient is φ = 1130876992.

The previous prime is 1131305423. The next prime is 1131305437. The reversal of 1131305431 is 1345031311.

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 1131305431 - 2³ = 1131305423 is a prime.

It is a super-2 number, since 2×1131305431² = 2559703956420191522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1131305437) 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, 210235 + ... + 215548.

It is an arithmetic number, because the mean of its divisors is an integer number (282933468).

Almost surely, 2^1131305431 is an apocalyptic number.

1131305431 is a deficient number, since it is larger than the sum of its proper divisors (428441).

1131305431 is an equidigital number, since it uses as much as digits as its factorization.

1131305431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 428440.

The product of its (nonzero) digits is 540, while the sum is 22.

The square root of 1131305431 is about 33634.8841383466. The cubic root of 1131305431 is about 1041.9813777567.

Adding to 1131305431 its reverse (1345031311), we get a palindrome (2476336742).

The spelling of 1131305431 in words is "one billion, one hundred thirty-one million, three hundred five thousand, four hundred thirty-one".