16689943 has 4 divisors (see below), whose sum is σ = 16703568. Its totient is φ = 16676320.

The previous prime is 16689941. The next prime is 16690001. The reversal of 16689943 is 34998661.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34998661 = 797 ⋅43913.

It is a cyclic number.

It is not a de Polignac number, because 16689943 - 2¹ = 16689941 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16689893 and 16689902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16689941) 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, 4771 + ... + 7492.

It is an arithmetic number, because the mean of its divisors is an integer number (4175892).

Almost surely, 2^16689943 is an apocalyptic number.

16689943 is a deficient number, since it is larger than the sum of its proper divisors (13625).

16689943 is a wasteful number, since it uses less digits than its factorization.

16689943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13624.

The product of its digits is 279936, while the sum is 46.

The square root of 16689943 is about 4085.3326669930. The cubic root of 16689943 is about 255.5553346424. Note that the first 3 decimals are identical.

It can be divided in two parts, 1668 and 9943, that added together give a palindrome (11611).

The spelling of 16689943 in words is "sixteen million, six hundred eighty-nine thousand, nine hundred forty-three".