1131545321 has 4 divisors (see below), whose sum is σ = 1133637444. Its totient is φ = 1129453200.

The previous prime is 1131545309. The next prime is 1131545341. The reversal of 1131545321 is 1235451311.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1235451311 = 3109 ⋅397379.

It can be written as a sum of positive squares in 2 ways, for example, as 572932096 + 558613225 = 23936^2 + 23635^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1131545321 is a prime.

It is a super-3 number, since 3×1131545321³ (a number of 28 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1131545341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1045250 + ... + 1046331.

It is an arithmetic number, because the mean of its divisors is an integer number (283409361).

Almost surely, 2^1131545321 is an apocalyptic number.

It is an amenable number.

1131545321 is a deficient number, since it is larger than the sum of its proper divisors (2092123).

1131545321 is an equidigital number, since it uses as much as digits as its factorization.

1131545321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2092122.

The product of its digits is 1800, while the sum is 26.

The square root of 1131545321 is about 33638.4500386091. The cubic root of 1131545321 is about 1042.0550222504.

Adding to 1131545321 its reverse (1235451311), we get a palindrome (2366996632).

The spelling of 1131545321 in words is "one billion, one hundred thirty-one million, five hundred forty-five thousand, three hundred twenty-one".