20211099999917 has 2 divisors, whose sum is σ = 20211099999918. Its totient is φ = 20211099999916.

The previous prime is 20211099999833. The next prime is 20211099999967. The reversal of 20211099999917 is 71999999011202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10512989155876 + 9698110844041 = 3242374^2 + 3114179^2 .

It is a cyclic number.

It is not a de Polignac number, because 20211099999917 - 2¹⁴ = 20211099983533 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20211099999967) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105549999958 + 10105549999959.

It is an arithmetic number, because the mean of its divisors is an integer number (10105549999959).

Almost surely, 2^{20211099999917} is an apocalyptic number.

It is an amenable number.

20211099999917 is a deficient number, since it is larger than the sum of its proper divisors (1).

20211099999917 is an equidigital number, since it uses as much as digits as its factorization.

20211099999917 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 14880348, while the sum is 68.

The spelling of 20211099999917 in words is "twenty trillion, two hundred eleven billion, ninety-nine million, nine hundred ninety-nine thousand, nine hundred seventeen".