21023209014881 has 2 divisors, whose sum is σ = 21023209014882. Its totient is φ = 21023209014880.

The previous prime is 21023209014853. The next prime is 21023209014883. The reversal of 21023209014881 is 18841090232012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16800940221025 + 4222268793856 = 4098895^2 + 2054816^2 .

It is a cyclic number.

It is not a de Polignac number, because 21023209014881 - 2¹⁰ = 21023209013857 is a prime.

It is a super-2 number, since 2×21023209014881² (a number of 27 digits) contains 22 as substring.

Together with 21023209014883, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21023209014883) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10511604507440 + 10511604507441.

It is an arithmetic number, because the mean of its divisors is an integer number (10511604507441).

Almost surely, 2^{21023209014881} is an apocalyptic number.

It is an amenable number.

21023209014881 is a deficient number, since it is larger than the sum of its proper divisors (1).

21023209014881 is an equidigital number, since it uses as much as digits as its factorization.

21023209014881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 55296, while the sum is 41.

Adding to 21023209014881 its reverse (18841090232012), we get a palindrome (39864299246893).

The spelling of 21023209014881 in words is "twenty-one trillion, twenty-three billion, two hundred nine million, fourteen thousand, eight hundred eighty-one".