1131532221 has 4 divisors (see below), whose sum is σ = 1508709632. Its totient is φ = 754354812.

The previous prime is 1131532217. The next prime is 1131532231. The reversal of 1131532221 is 1222351311.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 1222351311 = 3 ⋅407450437.

It is not a de Polignac number, because 1131532221 - 2² = 1131532217 is a prime.

It is a super-2 number, since 2×1131532221² = 2560730334322385682, 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 (1131532231) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 188588701 + ... + 188588706.

It is an arithmetic number, because the mean of its divisors is an integer number (377177408).

Almost surely, 2^1131532221 is an apocalyptic number.

It is an amenable number.

1131532221 is a deficient number, since it is larger than the sum of its proper divisors (377177411).

1131532221 is an equidigital number, since it uses as much as digits as its factorization.

1131532221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 377177410.

The product of its digits is 360, while the sum is 21.

The square root of 1131532221 is about 33638.2553203938. The cubic root of 1131532221 is about 1042.0510009139.

Adding to 1131532221 its reverse (1222351311), we get a palindrome (2353883532).

The spelling of 1131532221 in words is "one billion, one hundred thirty-one million, five hundred thirty-two thousand, two hundred twenty-one".