2121201305021 has 2 divisors, whose sum is σ = 2121201305022. Its totient is φ = 2121201305020.

The previous prime is 2121201304997. The next prime is 2121201305053. The reversal of 2121201305021 is 1205031021212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 2110877728996 + 10323576025 = 1452886^2 + 101605^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2121201305021 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2121201304984 and 2121201305002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2121201305621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1060600652510 + 1060600652511.

It is an arithmetic number, because the mean of its divisors is an integer number (1060600652511).

Almost surely, 2^{2121201305021} is an apocalyptic number.

It is an amenable number.

2121201305021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2121201305021 is an equidigital number, since it uses as much as digits as its factorization.

2121201305021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 240, while the sum is 20.

Adding to 2121201305021 its reverse (1205031021212), we get a palindrome (3326232326233).

The spelling of 2121201305021 in words is "two trillion, one hundred twenty-one billion, two hundred one million, three hundred five thousand, twenty-one".