21201221012071 has 2 divisors, whose sum is σ = 21201221012072. Its totient is φ = 21201221012070.

The previous prime is 21201221012053. The next prime is 21201221012233. The reversal of 21201221012071 is 17021012210212.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21201221012071 - 2¹¹ = 21201221010023 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21201221912071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10600610506035 + 10600610506036.

It is an arithmetic number, because the mean of its divisors is an integer number (10600610506036).

Almost surely, 2^{21201221012071} is an apocalyptic number.

21201221012071 is a deficient number, since it is larger than the sum of its proper divisors (1).

21201221012071 is an equidigital number, since it uses as much as digits as its factorization.

21201221012071 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 224, while the sum is 22.

Adding to 21201221012071 its reverse (17021012210212), we get a palindrome (38222233222283).

The spelling of 21201221012071 in words is "twenty-one trillion, two hundred one billion, two hundred twenty-one million, twelve thousand, seventy-one".