16221117 has 32 divisors (see below), whose sum is σ = 25482240. Its totient is φ = 9072000.

The previous prime is 16221113. The next prime is 16221119. The reversal of 16221117 is 71112261.

It is a happy number.

It is not a de Polignac number, because 16221117 - 2² = 16221113 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 16221093 and 16221102.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16221113) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 25392 + ... + 26022.

It is an arithmetic number, because the mean of its divisors is an integer number (796320).

Almost surely, 2^16221117 is an apocalyptic number.

It is an amenable number.

16221117 is a deficient number, since it is larger than the sum of its proper divisors (9261123).

16221117 is a wasteful number, since it uses less digits than its factorization.

16221117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 705.

The product of its digits is 168, while the sum is 21.

The square root of 16221117 is about 4027.5447855983. The cubic root of 16221117 is about 253.1396948640.

Adding to 16221117 its reverse (71112261), we get a palindrome (87333378).

The spelling of 16221117 in words is "sixteen million, two hundred twenty-one thousand, one hundred seventeen".