16398894217 has 2 divisors, whose sum is σ = 16398894218. Its totient is φ = 16398894216.

The previous prime is 16398894203. The next prime is 16398894227. The reversal of 16398894217 is 71249889361.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 16296054336 + 102839881 = 127656^2 + 10141^2 .

It is a cyclic number.

It is not a de Polignac number, because 16398894217 - 2⁷ = 16398894089 is a prime.

It is not a weakly prime, because it can be changed into another prime (16398894227) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8199447108 + 8199447109.

It is an arithmetic number, because the mean of its divisors is an integer number (8199447109).

Almost surely, 2^16398894217 is an apocalyptic number.

It is an amenable number.

16398894217 is a deficient number, since it is larger than the sum of its proper divisors (1).

16398894217 is an equidigital number, since it uses as much as digits as its factorization.

16398894217 is an evil number, because the sum of its binary digits is even.

The product of its digits is 5225472, while the sum is 58.

The spelling of 16398894217 in words is "sixteen billion, three hundred ninety-eight million, eight hundred ninety-four thousand, two hundred seventeen".