16689555 has 12 divisors (see below), whose sum is σ = 28928640. Its totient is φ = 8901072.

The previous prime is 16689523. The next prime is 16689593. The reversal of 16689555 is 55598661.

It is a happy number.

16689555 is a `hidden beast` number, since 16 + 6 + 89 + 555 = 666.

It is not a de Polignac number, because 16689555 - 2⁵ = 16689523 is a prime.

It is a Smith number, since the sum of its digits (45) coincides with the sum of the digits of its prime factors.

It is a Harshad number since it is a multiple of its sum of digits (45), and also a Moran number because the ratio is a prime number: 370879 = 16689555 / (1 + 6 + 6 + 8 + 9 + 5 + 5 + 5).

It is a nialpdrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 16689555.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 185395 + ... + 185484.

It is an arithmetic number, because the mean of its divisors is an integer number (2410720).

Almost surely, 2^16689555 is an apocalyptic number.

16689555 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

16689555 is a deficient number, since it is larger than the sum of its proper divisors (12239085).

16689555 is a wasteful number, since it uses less digits than its factorization.

16689555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 370890 (or 370887 counting only the distinct ones).

The product of its digits is 324000, while the sum is 45.

The square root of 16689555 is about 4085.2851797641. The cubic root of 16689555 is about 255.5533542834.

The spelling of 16689555 in words is "sixteen million, six hundred eighty-nine thousand, five hundred fifty-five".