19965217033217 has 2 divisors, whose sum is σ = 19965217033218. Its totient is φ = 19965217033216.

The previous prime is 19965217033189. The next prime is 19965217033231. The reversal of 19965217033217 is 71233071256991.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19871615302081 + 93601731136 = 4457759^2 + 305944^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19965217033217 is a prime.

It is not a weakly prime, because it can be changed into another prime (19965217033277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9982608516608 + 9982608516609.

It is an arithmetic number, because the mean of its divisors is an integer number (9982608516609).

Almost surely, 2^{19965217033217} is an apocalyptic number.

It is an amenable number.

19965217033217 is a deficient number, since it is larger than the sum of its proper divisors (1).

19965217033217 is an equidigital number, since it uses as much as digits as its factorization.

19965217033217 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4286520, while the sum is 56.

The spelling of 19965217033217 in words is "nineteen trillion, nine hundred sixty-five billion, two hundred seventeen million, thirty-three thousand, two hundred seventeen".