16330311212221 has 2 divisors, whose sum is σ = 16330311212222. Its totient is φ = 16330311212220.

The previous prime is 16330311212161. The next prime is 16330311212227. The reversal of 16330311212221 is 12221211303361.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12058603502500 + 4271707709721 = 3472550^2 + 2066811^2 .

It is an emirp because it is prime and its reverse (12221211303361) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16330311212221 - 2¹¹ = 16330311210173 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16330311212221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16330311212227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8165155606110 + 8165155606111.

It is an arithmetic number, because the mean of its divisors is an integer number (8165155606111).

Almost surely, 2^{16330311212221} is an apocalyptic number.

It is an amenable number.

16330311212221 is a deficient number, since it is larger than the sum of its proper divisors (1).

16330311212221 is an equidigital number, since it uses as much as digits as its factorization.

16330311212221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 28.

Adding to 16330311212221 its reverse (12221211303361), we get a palindrome (28551522515582).

The spelling of 16330311212221 in words is "sixteen trillion, three hundred thirty billion, three hundred eleven million, two hundred twelve thousand, two hundred twenty-one".