216936009 has 16 divisors (see below), whose sum is σ = 321745600. Its totient is φ = 144462528.

The previous prime is 216935959. The next prime is 216936029. The reversal of 216936009 is 900639612.

It is not a de Polignac number, because 216936009 - 2⁸ = 216935753 is a prime.

It is a super-2 number, since 2×216936009² = 94122464001696162, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (216936029) 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, 23262 + ... + 31224.

It is an arithmetic number, because the mean of its divisors is an integer number (20109100).

Almost surely, 2^216936009 is an apocalyptic number.

It is an amenable number.

216936009 is a deficient number, since it is larger than the sum of its proper divisors (104809591).

216936009 is a wasteful number, since it uses less digits than its factorization.

216936009 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8981 (or 8975 counting only the distinct ones).

The product of its (nonzero) digits is 17496, while the sum is 36.

The square root of 216936009 is about 14728.7477064413. The cubic root of 216936009 is about 600.8654261292.

The spelling of 216936009 in words is "two hundred sixteen million, nine hundred thirty-six thousand, nine".