20211113222161 has 2 divisors, whose sum is σ = 20211113222162. Its totient is φ = 20211113222160.

The previous prime is 20211113222159. The next prime is 20211113222239. The reversal of 20211113222161 is 16122231111202.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18316859232400 + 1894253989761 = 4279820^2 + 1376319^2 .

It is a cyclic number.

It is not a de Polignac number, because 20211113222161 - 2¹ = 20211113222159 is a prime.

It is a super-2 number, since 2×20211113222161² (a number of 27 digits) contains 22 as substring.

Together with 20211113222159, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20211113222101) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105556611080 + 10105556611081.

It is an arithmetic number, because the mean of its divisors is an integer number (10105556611081).

Almost surely, 2^{20211113222161} is an apocalyptic number.

It is an amenable number.

20211113222161 is a deficient number, since it is larger than the sum of its proper divisors (1).

20211113222161 is an equidigital number, since it uses as much as digits as its factorization.

20211113222161 is an evil number, because the sum of its binary digits is even.

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

Adding to 20211113222161 its reverse (16122231111202), we get a palindrome (36333344333363).

The spelling of 20211113222161 in words is "twenty trillion, two hundred eleven billion, one hundred thirteen million, two hundred twenty-two thousand, one hundred sixty-one".