21211100111017 has 2 divisors, whose sum is σ = 21211100111018. Its totient is φ = 21211100111016.

The previous prime is 21211100110973. The next prime is 21211100111023. The reversal of 21211100111017 is 71011100111212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17058915499536 + 4152184611481 = 4130244^2 + 2037691^2 .

It is a cyclic number.

It is not a de Polignac number, because 21211100111017 - 2¹⁵ = 21211100078249 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21211100110985 and 21211100111003.

It is not a weakly prime, because it can be changed into another prime (21211100111077) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10605550055508 + 10605550055509.

It is an arithmetic number, because the mean of its divisors is an integer number (10605550055509).

Almost surely, 2^{21211100111017} is an apocalyptic number.

It is an amenable number.

21211100111017 is a deficient number, since it is larger than the sum of its proper divisors (1).

21211100111017 is an equidigital number, since it uses as much as digits as its factorization.

21211100111017 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28, while the sum is 19.

Adding to 21211100111017 its reverse (71011100111212), we get a palindrome (92222200222229).

The spelling of 21211100111017 in words is "twenty-one trillion, two hundred eleven billion, one hundred million, one hundred eleven thousand, seventeen".