16891919 has 4 divisors (see below), whose sum is σ = 18427560. Its totient is φ = 15356280.

The previous prime is 16891879. The next prime is 16891921. The reversal of 16891919 is 91919861.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 16891919 - 2⁸ = 16891663 is a prime.

It is a super-2 number, since 2×16891919² = 570673855005122, which contains 22 as substring.

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 16891919.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16891219) 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, 767804 + ... + 767825.

It is an arithmetic number, because the mean of its divisors is an integer number (4606890).

Almost surely, 2^16891919 is an apocalyptic number.

16891919 is a deficient number, since it is larger than the sum of its proper divisors (1535641).

16891919 is a wasteful number, since it uses less digits than its factorization.

16891919 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1535640.

The product of its digits is 34992, while the sum is 44.

The square root of 16891919 is about 4109.9779804763. The cubic root of 16891919 is about 256.5820850966.

The spelling of 16891919 in words is "sixteen million, eight hundred ninety-one thousand, nine hundred nineteen".