211121201201621 has 2 divisors, whose sum is σ = 211121201201622. Its totient is φ = 211121201201620.

The previous prime is 211121201201611. The next prime is 211121201201699. The reversal of 211121201201621 is 126102102121112.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 107198875908721 + 103922325292900 = 10353689^2 + 10194230^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-211121201201621 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (211121201201611) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 105560600600810 + 105560600600811.

It is an arithmetic number, because the mean of its divisors is an integer number (105560600600811).

Almost surely, 2^{211121201201621} is an apocalyptic number.

It is an amenable number.

211121201201621 is a deficient number, since it is larger than the sum of its proper divisors (1).

211121201201621 is an equidigital number, since it uses as much as digits as its factorization.

211121201201621 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 192, while the sum is 23.

Adding to 211121201201621 its reverse (126102102121112), we get a palindrome (337223303322733).

The spelling of 211121201201621 in words is "two hundred eleven trillion, one hundred twenty-one billion, two hundred one million, two hundred one thousand, six hundred twenty-one".