2222201621 has 2 divisors, whose sum is σ = 2222201622. Its totient is φ = 2222201620.

The previous prime is 2222201549. The next prime is 2222201623. The reversal of 2222201621 is 1261022222.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1289815396 + 932386225 = 35914^2 + 30535^2 .

It is a cyclic number.

It is not a de Polignac number, because 2222201621 - 2¹⁰ = 2222200597 is a prime.

Together with 2222201623, it forms a pair of twin primes.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 2222201593 and 2222201602.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2222201623) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1111100810 + 1111100811.

It is an arithmetic number, because the mean of its divisors is an integer number (1111100811).

Almost surely, 2^2222201621 is an apocalyptic number.

It is an amenable number.

2222201621 is a deficient number, since it is larger than the sum of its proper divisors (1).

2222201621 is an equidigital number, since it uses as much as digits as its factorization.

2222201621 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 20.

The square root of 2222201621 is about 47140.2335696377. The cubic root of 2222201621 is about 1304.9518478242.

Adding to 2222201621 its reverse (1261022222), we get a palindrome (3483223843).

The spelling of 2222201621 in words is "two billion, two hundred twenty-two million, two hundred one thousand, six hundred twenty-one".