20112220122121 has 2 divisors, whose sum is σ = 20112220122122. Its totient is φ = 20112220122120.

The previous prime is 20112220122119. The next prime is 20112220122157. The reversal of 20112220122121 is 12122102221102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17990653088521 + 2121567033600 = 4241539^2 + 1456560^2 .

It is a cyclic number.

It is not a de Polignac number, because 20112220122121 - 2¹ = 20112220122119 is a prime.

Together with 20112220122119, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (20112220122191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10056110061060 + 10056110061061.

It is an arithmetic number, because the mean of its divisors is an integer number (10056110061061).

Almost surely, 2^{20112220122121} is an apocalyptic number.

It is an amenable number.

20112220122121 is a deficient number, since it is larger than the sum of its proper divisors (1).

20112220122121 is an equidigital number, since it uses as much as digits as its factorization.

20112220122121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 20112220122121 its reverse (12122102221102), we get a palindrome (32234322343223).

It can be divided in two parts, 20112220 and 122121, that added together give a triangular number (20234341 = T₆₃₆₁).

The spelling of 20112220122121 in words is "twenty trillion, one hundred twelve billion, two hundred twenty million, one hundred twenty-two thousand, one hundred twenty-one".