1311433221 has 32 divisors (see below), whose sum is σ = 2053168128. Its totient is φ = 728985600.

The previous prime is 1311433199. The next prime is 1311433241. The reversal of 1311433221 is 1223341131.

It is not a de Polignac number, because 1311433221 - 2¹³ = 1311425029 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311433241) 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 31 ways as a sum of consecutive naturals, for example, 229246 + ... + 234896.

It is an arithmetic number, because the mean of its divisors is an integer number (64161504).

Almost surely, 2^1311433221 is an apocalyptic number.

It is an amenable number.

1311433221 is a deficient number, since it is larger than the sum of its proper divisors (741734907).

1311433221 is a wasteful number, since it uses less digits than its factorization.

1311433221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5961.

The product of its digits is 432, while the sum is 21.

The square root of 1311433221 is about 36213.7159236663. The cubic root of 1311433221 is about 1094.5830709789.

Adding to 1311433221 its reverse (1223341131), we get a palindrome (2534774352).

The spelling of 1311433221 in words is "one billion, three hundred eleven million, four hundred thirty-three thousand, two hundred twenty-one".