16628109 has 4 divisors (see below), whose sum is σ = 22170816. Its totient is φ = 11085404.

The previous prime is 16628099. The next prime is 16628111. The reversal of 16628109 is 90182661.

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 16628109 - 2⁴ = 16628093 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 16628109.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16628189) 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, 2771349 + ... + 2771354.

It is an arithmetic number, because the mean of its divisors is an integer number (5542704).

Almost surely, 2^16628109 is an apocalyptic number.

It is an amenable number.

16628109 is a deficient number, since it is larger than the sum of its proper divisors (5542707).

16628109 is an equidigital number, since it uses as much as digits as its factorization.

16628109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5542706.

The product of its (nonzero) digits is 5184, while the sum is 33.

The square root of 16628109 is about 4077.7578397938. The cubic root of 16628109 is about 255.2393446756.

The spelling of 16628109 in words is "sixteen million, six hundred twenty-eight thousand, one hundred nine".