1331210120021 has 2 divisors, whose sum is σ = 1331210120022. Its totient is φ = 1331210120020.

The previous prime is 1331210120017. The next prime is 1331210120059. The reversal of 1331210120021 is 1200210121331.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1323362640625 + 7847479396 = 1150375^2 + 88586^2 .

It is a cyclic number.

It is not a de Polignac number, because 1331210120021 - 2² = 1331210120017 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1331210120521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 665605060010 + 665605060011.

It is an arithmetic number, because the mean of its divisors is an integer number (665605060011).

Almost surely, 2^{1331210120021} is an apocalyptic number.

It is an amenable number.

1331210120021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1331210120021 is an equidigital number, since it uses as much as digits as its factorization.

1331210120021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 1331210120021 its reverse (1200210121331), we get a palindrome (2531420241352).

The spelling of 1331210120021 in words is "one trillion, three hundred thirty-one billion, two hundred ten million, one hundred twenty thousand, twenty-one".