2012210221621 has 2 divisors, whose sum is σ = 2012210221622. Its totient is φ = 2012210221620.

The previous prime is 2012210221613. The next prime is 2012210221667. The reversal of 2012210221621 is 1261220122102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1513357594596 + 498852627025 = 1230186^2 + 706295^2 .

It is a cyclic number.

It is not a de Polignac number, because 2012210221621 - 2³ = 2012210221613 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2012210221592 and 2012210221601.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2012280221621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1006105110810 + 1006105110811.

It is an arithmetic number, because the mean of its divisors is an integer number (1006105110811).

Almost surely, 2^{2012210221621} is an apocalyptic number.

It is an amenable number.

2012210221621 is a deficient number, since it is larger than the sum of its proper divisors (1).

2012210221621 is an equidigital number, since it uses as much as digits as its factorization.

2012210221621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 384, while the sum is 22.

Adding to 2012210221621 its reverse (1261220122102), we get a palindrome (3273430343723).

The spelling of 2012210221621 in words is "two trillion, twelve billion, two hundred ten million, two hundred twenty-one thousand, six hundred twenty-one".