1331323221 has 8 divisors (see below), whose sum is σ = 1779439360. Its totient is φ = 885377952.

The previous prime is 1331323207. The next prime is 1331323229. The reversal of 1331323221 is 1223231331.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1331323221 - 2⁹ = 1331322709 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1331323229) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 541285 + ... + 543738.

It is an arithmetic number, because the mean of its divisors is an integer number (222429920).

Almost surely, 2^1331323221 is an apocalyptic number.

It is an amenable number.

1331323221 is a deficient number, since it is larger than the sum of its proper divisors (448116139).

1331323221 is a wasteful number, since it uses less digits than its factorization.

1331323221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1085435.

The product of its digits is 648, while the sum is 21.

The square root of 1331323221 is about 36487.3021885697. The cubic root of 1331323221 is about 1100.0890343911.

Adding to 1331323221 its reverse (1223231331), we get a palindrome (2554554552).

The spelling of 1331323221 in words is "one billion, three hundred thirty-one million, three hundred twenty-three thousand, two hundred twenty-one".