216916897 has 16 divisors (see below), whose sum is σ = 231042240. Its totient is φ = 203297472.

The previous prime is 216916883. The next prime is 216916919. The reversal of 216916897 is 798619612.

It is a 6-Lehmer number, since φ(216916897) divides (216916897-1)⁶.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-216916897 is a prime.

It is a super-3 number, since 3×216916897³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 216916897.

It is not an unprimeable number, because it can be changed into a prime (216916807) 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, 245218 + ... + 246100.

It is an arithmetic number, because the mean of its divisors is an integer number (14440140).

Almost surely, 2^216916897 is an apocalyptic number.

216916897 is the 7873-rd centered heptagonal number.

It is an amenable number.

216916897 is a deficient number, since it is larger than the sum of its proper divisors (14125343).

216916897 is a wasteful number, since it uses less digits than its factorization.

216916897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1152.

The product of its digits is 326592, while the sum is 49.

The square root of 216916897 is about 14728.0988929325. The cubic root of 216916897 is about 600.8477802539.

The spelling of 216916897 in words is "two hundred sixteen million, nine hundred sixteen thousand, eight hundred ninety-seven".