216568641 has 8 divisors (see below), whose sum is σ = 290866464. Its totient is φ = 143324960.

The previous prime is 216568637. The next prime is 216568679. The reversal of 216568641 is 146865612.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 216568641 - 2² = 216568637 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 216568641.

It is not an unprimeable number, because it can be changed into a prime (216568691) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 263055 + ... + 263876.

It is an arithmetic number, because the mean of its divisors is an integer number (36358308).

Almost surely, 2^216568641 is an apocalyptic number.

It is an amenable number.

216568641 is a deficient number, since it is larger than the sum of its proper divisors (74297823).

216568641 is a wasteful number, since it uses less digits than its factorization.

216568641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 527071.

The product of its digits is 69120, while the sum is 39.

The square root of 216568641 is about 14716.2713008425. The cubic root of 216568641 is about 600.5260580811.

The spelling of 216568641 in words is "two hundred sixteen million, five hundred sixty-eight thousand, six hundred forty-one".