1611012122221 has 2 divisors, whose sum is σ = 1611012122222. Its totient is φ = 1611012122220.

The previous prime is 1611012122207. The next prime is 1611012122333. The reversal of 1611012122221 is 1222212101161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1583039559721 + 27972562500 = 1258189^2 + 167250^2 .

It is an emirp because it is prime and its reverse (1222212101161) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1611012122221 - 2¹³ = 1611012114029 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 1611012122192 and 1611012122201.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1611012128221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 805506061110 + 805506061111.

It is an arithmetic number, because the mean of its divisors is an integer number (805506061111).

Almost surely, 2^{1611012122221} is an apocalyptic number.

It is an amenable number.

1611012122221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1611012122221 is an equidigital number, since it uses as much as digits as its factorization.

1611012122221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 192, while the sum is 22.

Adding to 1611012122221 its reverse (1222212101161), we get a palindrome (2833224223382).

The spelling of 1611012122221 in words is "one trillion, six hundred eleven billion, twelve million, one hundred twenty-two thousand, two hundred twenty-one".