9999216 has 30 divisors (see below), whose sum is σ = 27984320. Its totient is φ = 3333024.

The previous prime is 9999193. The next prime is 9999217. The reversal of 9999216 is 6129999.

It is a happy number.

It is a super-2 number, since 2×9999216² = 199968641229312, which contains 22 as substring.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a nude number because it is divisible by every one of its digits.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (9999217) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 34576 + ... + 34863.

Almost surely, 2^9999216 is an apocalyptic number.

It is an amenable number.

9999216 is an abundant number, since it is smaller than the sum of its proper divisors (17985104).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

9999216 is a wasteful number, since it uses less digits than its factorization.

9999216 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69453 (or 69444 counting only the distinct ones).

The product of its digits is 78732, while the sum is 45.

The square root of 9999216 is about 3162.1536964544. The cubic root of 9999216 is about 215.4378386001.

The spelling of 9999216 in words is "nine million, nine hundred ninety-nine thousand, two hundred sixteen".