21210111201017 has 2 divisors, whose sum is σ = 21210111201018. Its totient is φ = 21210111201016.

The previous prime is 21210111200977. The next prime is 21210111201131. The reversal of 21210111201017 is 71010211101212.

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., 20170015138816 + 1040096062201 = 4491104^2 + 1019851^2 .

It is a cyclic number.

It is not a de Polignac number, because 21210111201017 - 2⁶ = 21210111200953 is a prime.

It is a super-3 number, since 3×21210111201017³ (a number of 41 digits) contains 333 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21210111201017.

It is not a weakly prime, because it can be changed into another prime (21210111204017) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605055600508 + 10605055600509.

It is an arithmetic number, because the mean of its divisors is an integer number (10605055600509).

Almost surely, 2^{21210111201017} is an apocalyptic number.

It is an amenable number.

21210111201017 is a deficient number, since it is larger than the sum of its proper divisors (1).

21210111201017 is an equidigital number, since it uses as much as digits as its factorization.

21210111201017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56, while the sum is 20.

Adding to 21210111201017 its reverse (71010211101212), we get a palindrome (92220322302229).

The spelling of 21210111201017 in words is "twenty-one trillion, two hundred ten billion, one hundred eleven million, two hundred one thousand, seventeen".