20100120217 has 2 divisors, whose sum is σ = 20100120218. Its totient is φ = 20100120216.

The previous prime is 20100120181. The next prime is 20100120283. The reversal of 20100120217 is 71202100102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 17145545481 + 2954574736 = 130941^2 + 54356^2 .

It is a cyclic number.

It is not a de Polignac number, because 20100120217 - 2²³ = 20091731609 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20100120217.

It is not a weakly prime, because it can be changed into another prime (20100120517) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10050060108 + 10050060109.

It is an arithmetic number, because the mean of its divisors is an integer number (10050060109).

Almost surely, 2^20100120217 is an apocalyptic number.

It is an amenable number.

20100120217 is a deficient number, since it is larger than the sum of its proper divisors (1).

20100120217 is an equidigital number, since it uses as much as digits as its factorization.

20100120217 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 16.

Adding to 20100120217 its reverse (71202100102), we get a palindrome (91302220319).

The spelling of 20100120217 in words is "twenty billion, one hundred million, one hundred twenty thousand, two hundred seventeen".