16633221 has 16 divisors (see below), whose sum is σ = 24606720. Its totient is φ = 9908720.

The previous prime is 16633207. The next prime is 16633223. The reversal of 16633221 is 12233661.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 16633221 - 2⁷ = 16633093 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 16633191 and 16633200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16633223) 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, 2325 + ... + 6218.

It is an arithmetic number, because the mean of its divisors is an integer number (1537920).

Almost surely, 2^16633221 is an apocalyptic number.

16633221 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

16633221 is a deficient number, since it is larger than the sum of its proper divisors (7973499).

16633221 is a wasteful number, since it uses less digits than its factorization.

16633221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8616.

The product of its digits is 1296, while the sum is 24.

The square root of 16633221 is about 4078.3846066795. The cubic root of 16633221 is about 255.2654981775.

Adding to 16633221 its reverse (12233661), we get a palindrome (28866882).

It can be divided in two parts, 1663 and 3221, that added together give a palindrome (4884).

The spelling of 16633221 in words is "sixteen million, six hundred thirty-three thousand, two hundred twenty-one".