21022101221281 has 2 divisors, whose sum is σ = 21022101221282. Its totient is φ = 21022101221280.

The previous prime is 21022101221263. The next prime is 21022101221323. The reversal of 21022101221281 is 18212210122012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20148607238400 + 873493982881 = 4488720^2 + 934609^2 .

It is a cyclic number.

It is not a de Polignac number, because 21022101221281 - 2³⁵ = 20987741482913 is a prime.

It is a super-2 number, since 2×21022101221281² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21022101221581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10511050610640 + 10511050610641.

It is an arithmetic number, because the mean of its divisors is an integer number (10511050610641).

Almost surely, 2^{21022101221281} is an apocalyptic number.

It is an amenable number.

21022101221281 is a deficient number, since it is larger than the sum of its proper divisors (1).

21022101221281 is an equidigital number, since it uses as much as digits as its factorization.

21022101221281 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 512, while the sum is 25.

Adding to 21022101221281 its reverse (18212210122012), we get a palindrome (39234311343293).

The spelling of 21022101221281 in words is "twenty-one trillion, twenty-two billion, one hundred one million, two hundred twenty-one thousand, two hundred eighty-one".