12211621621 has 2 divisors, whose sum is σ = 12211621622. Its totient is φ = 12211621620.

The previous prime is 12211621607. The next prime is 12211621691. The reversal of 12211621621 is 12612611221.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12207819121 + 3802500 = 110489^2 + 1950^2 .

It is a cyclic number.

It is not a de Polignac number, because 12211621621 - 2¹⁵ = 12211588853 is a prime.

It is a super-2 number, since 2×12211621621² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12211621601) 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, 6105810810 + 6105810811.

It is an arithmetic number, because the mean of its divisors is an integer number (6105810811).

Almost surely, 2^12211621621 is an apocalyptic number.

It is an amenable number.

12211621621 is a deficient number, since it is larger than the sum of its proper divisors (1).

12211621621 is an equidigital number, since it uses as much as digits as its factorization.

12211621621 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 576, while the sum is 25.

The spelling of 12211621621 in words is "twelve billion, two hundred eleven million, six hundred twenty-one thousand, six hundred twenty-one".