3217921387217 has 2 divisors, whose sum is σ = 3217921387218. Its totient is φ = 3217921387216.

The previous prime is 3217921387201. The next prime is 3217921387237. The reversal of 3217921387217 is 7127831297123.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1873733896336 + 1344187490881 = 1368844^2 + 1159391^2 .

It is an emirp because it is prime and its reverse (7127831297123) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 3217921387217 - 2⁴ = 3217921387201 is a prime.

It is not a weakly prime, because it can be changed into another prime (3217921387237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1608960693608 + 1608960693609.

It is an arithmetic number, because the mean of its divisors is an integer number (1608960693609).

Almost surely, 2^{3217921387217} is an apocalyptic number.

It is an amenable number.

3217921387217 is a deficient number, since it is larger than the sum of its proper divisors (1).

3217921387217 is an equidigital number, since it uses as much as digits as its factorization.

3217921387217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1778112, while the sum is 53.

The spelling of 3217921387217 in words is "three trillion, two hundred seventeen billion, nine hundred twenty-one million, three hundred eighty-seven thousand, two hundred seventeen".