21022121000521 has 2 divisors, whose sum is σ = 21022121000522. Its totient is φ = 21022121000520.

The previous prime is 21022121000519. The next prime is 21022121000527. The reversal of 21022121000521 is 12500012122012.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16189316724025 + 4832804276496 = 4023595^2 + 2198364^2 .

It is a cyclic number.

It is not a de Polignac number, because 21022121000521 - 2¹ = 21022121000519 is a prime.

Together with 21022121000519, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (21022121000527) 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, 10511060500260 + 10511060500261.

It is an arithmetic number, because the mean of its divisors is an integer number (10511060500261).

Almost surely, 2^{21022121000521} is an apocalyptic number.

It is an amenable number.

21022121000521 is a deficient number, since it is larger than the sum of its proper divisors (1).

21022121000521 is an equidigital number, since it uses as much as digits as its factorization.

21022121000521 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 160, while the sum is 19.

Adding to 21022121000521 its reverse (12500012122012), we get a palindrome (33522133122533).

The spelling of 21022121000521 in words is "twenty-one trillion, twenty-two billion, one hundred twenty-one million, five hundred twenty-one", and thus it is an aban number.