1131222031 has 4 divisors (see below), whose sum is σ = 1132181064. Its totient is φ = 1130263000.

The previous prime is 1131222017. The next prime is 1131222049. The reversal of 1131222031 is 1302221311.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1302221311 = 3221 ⋅404291.

It is a cyclic number.

It is not a de Polignac number, because 1131222031 - 2⁵ = 1131221999 is a prime.

It is a super-2 number, since 2×1131222031² = 2559326566839529922, 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 = 1131221996 and 1131222014.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1131222011) 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, 477745 + ... + 480106.

It is an arithmetic number, because the mean of its divisors is an integer number (283045266).

Almost surely, 2^1131222031 is an apocalyptic number.

1131222031 is a deficient number, since it is larger than the sum of its proper divisors (959033).

1131222031 is an equidigital number, since it uses as much as digits as its factorization.

1131222031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 959032.

The product of its (nonzero) digits is 72, while the sum is 16.

The square root of 1131222031 is about 33633.6443312348. The cubic root of 1131222031 is about 1041.9557721215.

Adding to 1131222031 its reverse (1302221311), we get a palindrome (2433443342).

The spelling of 1131222031 in words is "one billion, one hundred thirty-one million, two hundred twenty-two thousand, thirty-one".