221216017 has 4 divisors (see below), whose sum is σ = 241326576. Its totient is φ = 201105460.

The previous prime is 221216003. The next prime is 221216027. The reversal of 221216017 is 710612122.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 221216017 - 2¹¹ = 221213969 is a prime.

It is a Smith number, since the sum of its digits (22) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221216027) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10055263 + ... + 10055284.

It is an arithmetic number, because the mean of its divisors is an integer number (60331644).

Almost surely, 2^221216017 is an apocalyptic number.

It is an amenable number.

221216017 is a deficient number, since it is larger than the sum of its proper divisors (20110559).

221216017 is a wasteful number, since it uses less digits than its factorization.

221216017 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20110558.

The product of its (nonzero) digits is 336, while the sum is 22.

The square root of 221216017 is about 14873.3324107276. The cubic root of 221216017 is about 604.7912828746.

Adding to 221216017 its reverse (710612122), we get a palindrome (931828139).

The spelling of 221216017 in words is "two hundred twenty-one million, two hundred sixteen thousand, seventeen".