1331322221 has 2 divisors, whose sum is σ = 1331322222. Its totient is φ = 1331322220.

The previous prime is 1331322217. The next prime is 1331322247. The reversal of 1331322221 is 1222231331.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1088274121 + 243048100 = 32989^2 + 15590^2 .

It is a cyclic number.

It is not a de Polignac number, because 1331322221 - 2² = 1331322217 is a prime.

It is a super-2 number, since 2×1331322221² = 3544837712256745682, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 1331322193 and 1331322202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1331322281) 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 as a sum of consecutive naturals, namely, 665661110 + 665661111.

It is an arithmetic number, because the mean of its divisors is an integer number (665661111).

Almost surely, 2^1331322221 is an apocalyptic number.

It is an amenable number.

1331322221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331322221 is an equidigital number, since it uses as much as digits as its factorization.

1331322221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 432, while the sum is 20.

The square root of 1331322221 is about 36487.2884851697. The cubic root of 1331322221 is about 1100.0887589536.

Adding to 1331322221 its reverse (1222231331), we get a palindrome (2553553552).

The spelling of 1331322221 in words is "one billion, three hundred thirty-one million, three hundred twenty-two thousand, two hundred twenty-one".