3221812621 has 2 divisors, whose sum is σ = 3221812622. Its totient is φ = 3221812620.

The previous prime is 3221812619. The next prime is 3221812637. The reversal of 3221812621 is 1262181223.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1801578025 + 1420234596 = 42445^2 + 37686^2 .

It is an emirp because it is prime and its reverse (1262181223) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3221812621 - 2¹ = 3221812619 is a prime.

Together with 3221812619, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 3221812621.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (3221812921) 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, 1610906310 + 1610906311.

It is an arithmetic number, because the mean of its divisors is an integer number (1610906311).

Almost surely, 2^3221812621 is an apocalyptic number.

It is an amenable number.

3221812621 is a deficient number, since it is larger than the sum of its proper divisors (1).

3221812621 is an equidigital number, since it uses as much as digits as its factorization.

3221812621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2304, while the sum is 28.

The square root of 3221812621 is about 56761.0132132963. The cubic root of 3221812621 is about 1476.9532863313.

Adding to 3221812621 its reverse (1262181223), we get a palindrome (4483993844).

The spelling of 3221812621 in words is "three billion, two hundred twenty-one million, eight hundred twelve thousand, six hundred twenty-one".