1131031221 has 16 divisors (see below), whose sum is σ = 1611110400. Its totient is φ = 703671408.

The previous prime is 1131031219. The next prime is 1131031241. The reversal of 1131031221 is 1221301311.

It is a happy number.

It is not a de Polignac number, because 1131031221 - 2¹ = 1131031219 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1131031221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1131031241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 144261 + ... + 151898.

It is an arithmetic number, because the mean of its divisors is an integer number (100694400).

Almost surely, 2^1131031221 is an apocalyptic number.

It is an amenable number.

1131031221 is a deficient number, since it is larger than the sum of its proper divisors (480079179).

1131031221 is a wasteful number, since it uses less digits than its factorization.

1131031221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 296248.

The product of its (nonzero) digits is 36, while the sum is 15.

The square root of 1131031221 is about 33630.8076174213. The cubic root of 1131031221 is about 1041.8971845189.

Adding to 1131031221 its reverse (1221301311), we get a palindrome (2352332532).

The spelling of 1131031221 in words is "one billion, one hundred thirty-one million, thirty-one thousand, two hundred twenty-one".