1131303221 has 4 divisors (see below), whose sum is σ = 1138509132. Its totient is φ = 1124097312.

The previous prime is 1131303209. The next prime is 1131303247. The reversal of 1131303221 is 1223031311.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 356794321 + 774508900 = 18889^2 + 27830^2 .

It is a cyclic number.

It is not a de Polignac number, because 1131303221 - 2¹⁰ = 1131302197 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1131303221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1131305221) 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, 3602720 + ... + 3603033.

It is an arithmetic number, because the mean of its divisors is an integer number (284627283).

Almost surely, 2^1131303221 is an apocalyptic number.

It is an amenable number.

1131303221 is a deficient number, since it is larger than the sum of its proper divisors (7205911).

1131303221 is an equidigital number, since it uses as much as digits as its factorization.

1131303221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7205910.

The product of its (nonzero) digits is 108, while the sum is 17.

The square root of 1131303221 is about 33634.8512855342. The cubic root of 1131303221 is about 1041.9806992543.

Adding to 1131303221 its reverse (1223031311), we get a palindrome (2354334532).

The spelling of 1131303221 in words is "one billion, one hundred thirty-one million, three hundred three thousand, two hundred twenty-one".