1331320021121 has 2 divisors, whose sum is σ = 1331320021122. Its totient is φ = 1331320021120.

The previous prime is 1331320021103. The next prime is 1331320021133. The reversal of 1331320021121 is 1211200231331.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1034909463025 + 296410558096 = 1017305^2 + 544436^2 .

It is a cyclic number.

It is not a de Polignac number, because 1331320021121 - 2¹⁰ = 1331320020097 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1331320021093 and 1331320021102.

It is not a weakly prime, because it can be changed into another prime (1331320024121) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 665660010560 + 665660010561.

It is an arithmetic number, because the mean of its divisors is an integer number (665660010561).

Almost surely, 2^{1331320021121} is an apocalyptic number.

It is an amenable number.

1331320021121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331320021121 is an equidigital number, since it uses as much as digits as its factorization.

1331320021121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 216, while the sum is 20.

Adding to 1331320021121 its reverse (1211200231331), we get a palindrome (2542520252452).

The spelling of 1331320021121 in words is "one trillion, three hundred thirty-one billion, three hundred twenty million, twenty-one thousand, one hundred twenty-one".