1331532221 has 2 divisors, whose sum is σ = 1331532222. Its totient is φ = 1331532220.

The previous prime is 1331532211. The next prime is 1331532227. The reversal of 1331532221 is 1222351331.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1331155225 + 376996 = 36485^2 + 614^2 .

It is a cyclic number.

It is not a de Polignac number, because 1331532221 - 2²⁶ = 1264423357 is a prime.

It is a super-2 number, since 2×1331532221² = 3545956111122385682, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1331532227) 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, 665766110 + 665766111.

It is an arithmetic number, because the mean of its divisors is an integer number (665766111).

Almost surely, 2^1331532221 is an apocalyptic number.

It is an amenable number.

1331532221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331532221 is an equidigital number, since it uses as much as digits as its factorization.

1331532221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1080, while the sum is 23.

The square root of 1331532221 is about 36490.1660862211. The cubic root of 1331532221 is about 1100.1465978173.

Adding to 1331532221 its reverse (1222351331), we get a palindrome (2553883552).

The spelling of 1331532221 in words is "one billion, three hundred thirty-one million, five hundred thirty-two thousand, two hundred twenty-one".