16217217 has 6 divisors (see below), whose sum is σ = 23424882. Its totient is φ = 10811472.

The previous prime is 16217207. The next prime is 16217251. The reversal of 16217217 is 71271261.

It can be written as a sum of positive squares in only one way, i.e., 13660416 + 2556801 = 3696^2 + 1599^2 .

It is not a de Polignac number, because 16217217 - 2⁸ = 16216961 is a prime.

It is not an unprimeable number, because it can be changed into a prime (16217207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 900948 + ... + 900965.

It is an arithmetic number, because the mean of its divisors is an integer number (3904147).

Almost surely, 2^16217217 is an apocalyptic number.

It is an amenable number.

16217217 is a deficient number, since it is larger than the sum of its proper divisors (7207665).

16217217 is a wasteful number, since it uses less digits than its factorization.

16217217 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1801919 (or 1801916 counting only the distinct ones).

The product of its digits is 1176, while the sum is 27.

The square root of 16217217 is about 4027.0605905549. The cubic root of 16217217 is about 253.1194060035.

Adding to 16217217 its reverse (71271261), we get a palindrome (87488478).

The spelling of 16217217 in words is "sixteen million, two hundred seventeen thousand, two hundred seventeen".