21012221020127 has 2 divisors, whose sum is σ = 21012221020128. Its totient is φ = 21012221020126.

The previous prime is 21012221020073. The next prime is 21012221020129. The reversal of 21012221020127 is 72102012221012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21012221020127 - 2¹⁴ = 21012221003743 is a prime.

It is a super-2 number, since 2×21012221020127² (a number of 27 digits) contains 22 as substring.

Together with 21012221020129, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21012221020129) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10506110510063 + 10506110510064.

It is an arithmetic number, because the mean of its divisors is an integer number (10506110510064).

Almost surely, 2^{21012221020127} is an apocalyptic number.

21012221020127 is a deficient number, since it is larger than the sum of its proper divisors (1).

21012221020127 is an equidigital number, since it uses as much as digits as its factorization.

21012221020127 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 448, while the sum is 23.

Adding to 21012221020127 its reverse (72102012221012), we get a palindrome (93114233241139).

The spelling of 21012221020127 in words is "twenty-one trillion, twelve billion, two hundred twenty-one million, twenty thousand, one hundred twenty-seven".