21122102161 has 2 divisors, whose sum is σ = 21122102162. Its totient is φ = 21122102160.

The previous prime is 21122102117. The next prime is 21122102171. The reversal of 21122102161 is 16120122112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14180046400 + 6942055761 = 119080^2 + 83319^2 .

It is a cyclic number.

It is not a de Polignac number, because 21122102161 - 2¹⁷ = 21121971089 is a prime.

It is a super-2 number, since 2×21122102161² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21122102171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10561051080 + 10561051081.

It is an arithmetic number, because the mean of its divisors is an integer number (10561051081).

Almost surely, 2^21122102161 is an apocalyptic number.

It is an amenable number.

21122102161 is a deficient number, since it is larger than the sum of its proper divisors (1).

21122102161 is an equidigital number, since it uses as much as digits as its factorization.

21122102161 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 21122102161 its reverse (16120122112), we get a palindrome (37242224273).

The spelling of 21122102161 in words is "twenty-one billion, one hundred twenty-two million, one hundred two thousand, one hundred sixty-one".