21021022212217 has 2 divisors, whose sum is σ = 21021022212218. Its totient is φ = 21021022212216.

The previous prime is 21021022212209. The next prime is 21021022212221. The reversal of 21021022212217 is 71221222012012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 12190264999936 + 8830757212281 = 3491456^2 + 2971659^2 .

It is a cyclic number.

It is not a de Polignac number, because 21021022212217 - 2³ = 21021022212209 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21021022212191 and 21021022212200.

It is not a weakly prime, because it can be changed into another prime (21021022212517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510511106108 + 10510511106109.

It is an arithmetic number, because the mean of its divisors is an integer number (10510511106109).

Almost surely, 2^{21021022212217} is an apocalyptic number.

It is an amenable number.

21021022212217 is a deficient number, since it is larger than the sum of its proper divisors (1).

21021022212217 is an equidigital number, since it uses as much as digits as its factorization.

21021022212217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 896, while the sum is 25.

Adding to 21021022212217 its reverse (71221222012012), we get a palindrome (92242244224229).

The spelling of 21021022212217 in words is "twenty-one trillion, twenty-one billion, twenty-two million, two hundred twelve thousand, two hundred seventeen".