16630221 has 4 divisors (see below), whose sum is σ = 22173632. Its totient is φ = 11086812.

The previous prime is 16630193. The next prime is 16630223. The reversal of 16630221 is 12203661.

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 not a de Polignac number, because 16630221 - 2⁶ = 16630157 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16630223) 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, 2771701 + ... + 2771706.

It is an arithmetic number, because the mean of its divisors is an integer number (5543408).

Almost surely, 2^16630221 is an apocalyptic number.

It is an amenable number.

16630221 is a deficient number, since it is larger than the sum of its proper divisors (5543411).

16630221 is an equidigital number, since it uses as much as digits as its factorization.

16630221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5543410.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 16630221 is about 4078.0167974151. The cubic root of 16630221 is about 255.2501505280.

Adding to 16630221 its reverse (12203661), we get a palindrome (28833882).

The spelling of 16630221 in words is "sixteen million, six hundred thirty thousand, two hundred twenty-one".