16891111 has 4 divisors (see below), whose sum is σ = 16912800. Its totient is φ = 16869424.

The previous prime is 16891109. The next prime is 16891117. The reversal of 16891111 is 11119861.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11119861 = 139 ⋅79999.

It is a cyclic number.

It is not a de Polignac number, because 16891111 - 2¹ = 16891109 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 16891111.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16891117) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 9631 + ... + 11248.

It is an arithmetic number, because the mean of its divisors is an integer number (4228200).

Almost surely, 2^16891111 is an apocalyptic number.

16891111 is a deficient number, since it is larger than the sum of its proper divisors (21689).

16891111 is an equidigital number, since it uses as much as digits as its factorization.

16891111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21688.

The product of its digits is 432, while the sum is 28.

The square root of 16891111 is about 4109.8796819372. The cubic root of 16891111 is about 256.5779939563.

The spelling of 16891111 in words is "sixteen million, eight hundred ninety-one thousand, one hundred eleven".