1331021112221 has 2 divisors, whose sum is σ = 1331021112222. Its totient is φ = 1331021112220.

The previous prime is 1331021112217. The next prime is 1331021112263. The reversal of 1331021112221 is 1222111201331.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1264657684900 + 66363427321 = 1124570^2 + 257611^2 .

It is a cyclic number.

It is not a de Polignac number, because 1331021112221 - 2² = 1331021112217 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1331021112193 and 1331021112202.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1331021117221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 665510556110 + 665510556111.

It is an arithmetic number, because the mean of its divisors is an integer number (665510556111).

Almost surely, 2^{1331021112221} is an apocalyptic number.

It is an amenable number.

1331021112221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331021112221 is an equidigital number, since it uses as much as digits as its factorization.

1331021112221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 20.

Adding to 1331021112221 its reverse (1222111201331), we get a palindrome (2553132313552).

The spelling of 1331021112221 in words is "one trillion, three hundred thirty-one billion, twenty-one million, one hundred twelve thousand, two hundred twenty-one".