20211611652217 has 2 divisors, whose sum is σ = 20211611652218. Its totient is φ = 20211611652216.

The previous prime is 20211611652191. The next prime is 20211611652227. The reversal of 20211611652217 is 71225611611202.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15686542469376 + 4525069182841 = 3960624^2 + 2127221^2 .

It is a cyclic number.

It is not a de Polignac number, because 20211611652217 - 2²³ = 20211603263609 is a prime.

It is a super-2 number, since 2×20211611652217² (a number of 27 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (20211611652227) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10105805826108 + 10105805826109.

It is an arithmetic number, because the mean of its divisors is an integer number (10105805826109).

Almost surely, 2^{20211611652217} is an apocalyptic number.

It is an amenable number.

20211611652217 is a deficient number, since it is larger than the sum of its proper divisors (1).

20211611652217 is an equidigital number, since it uses as much as digits as its factorization.

20211611652217 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20160, while the sum is 37.

The spelling of 20211611652217 in words is "twenty trillion, two hundred eleven billion, six hundred eleven million, six hundred fifty-two thousand, two hundred seventeen".