216906717 has 16 divisors (see below), whose sum is σ = 306023360. Its totient is φ = 136276992.

The previous prime is 216906673. The next prime is 216906727. The reversal of 216906717 is 717609612.

It is not a de Polignac number, because 216906717 - 2⁷ = 216906589 is a prime.

It is a super-3 number, since 3×216906717³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216906727) 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, 1143 + ... + 20859.

It is an arithmetic number, because the mean of its divisors is an integer number (19126460).

Almost surely, 2^216906717 is an apocalyptic number.

It is an amenable number.

216906717 is a deficient number, since it is larger than the sum of its proper divisors (89116643).

216906717 is a wasteful number, since it uses less digits than its factorization.

216906717 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19932.

The product of its (nonzero) digits is 31752, while the sum is 39.

The square root of 216906717 is about 14727.7532909809. The cubic root of 216906717 is about 600.8383807616.

The spelling of 216906717 in words is "two hundred sixteen million, nine hundred six thousand, seven hundred seventeen".