989817217 has 16 divisors (see below), whose sum is σ = 1062072000. Its totient is φ = 919655424.

The previous prime is 989817181. The next prime is 989817233. The reversal of 989817217 is 712718989.

It is a cyclic number.

It is not a de Polignac number, because 989817217 - 2¹⁹ = 989292929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (989817277) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 664009 + ... + 665497.

It is an arithmetic number, because the mean of its divisors is an integer number (66379500).

Almost surely, 2^989817217 is an apocalyptic number.

It is an amenable number.

989817217 is a deficient number, since it is larger than the sum of its proper divisors (72254783).

989817217 is a wasteful number, since it uses less digits than its factorization.

989817217 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2160.

The product of its digits is 508032, while the sum is 52.

The square root of 989817217 is about 31461.3606984822. The cubic root of 989817217 is about 996.5941523710.

The spelling of 989817217 in words is "nine hundred eighty-nine million, eight hundred seventeen thousand, two hundred seventeen".