1131252431 has 4 divisors (see below), whose sum is σ = 1131686664. Its totient is φ = 1130818200.

The previous prime is 1131252413. The next prime is 1131252433. The reversal of 1131252431 is 1342521311.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1342521311 = 317 ⋅4235083.

It is a cyclic number.

It is not a de Polignac number, because 1131252431 - 2¹⁴ = 1131236047 is a prime.

It is a super-2 number, since 2×1131252431² = 2559464125286819522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1131252397 and 1131252406.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1131252433) 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 3 ways as a sum of consecutive naturals, for example, 213185 + ... + 218426.

It is an arithmetic number, because the mean of its divisors is an integer number (282921666).

Almost surely, 2^1131252431 is an apocalyptic number.

1131252431 is a deficient number, since it is larger than the sum of its proper divisors (434233).

1131252431 is an equidigital number, since it uses as much as digits as its factorization.

1131252431 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 434232.

The product of its digits is 720, while the sum is 23.

The square root of 1131252431 is about 33634.0962566263. The cubic root of 1131252431 is about 1041.9651057362.

Adding to 1131252431 its reverse (1342521311), we get a palindrome (2473773742).

The spelling of 1131252431 in words is "one billion, one hundred thirty-one million, two hundred fifty-two thousand, four hundred thirty-one".