16399543 has 4 divisors (see below), whose sum is σ = 17364240. Its totient is φ = 15434848.

The previous prime is 16399541. The next prime is 16399561. The reversal of 16399543 is 34599361.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 34599361 = 19 ⋅1821019.

It is a cyclic number.

It is not a de Polignac number, because 16399543 - 2¹ = 16399541 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 16399496 and 16399505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16399541) 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, 482323 + ... + 482356.

It is an arithmetic number, because the mean of its divisors is an integer number (4341060).

Almost surely, 2^16399543 is an apocalyptic number.

16399543 is a deficient number, since it is larger than the sum of its proper divisors (964697).

16399543 is an equidigital number, since it uses as much as digits as its factorization.

16399543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 964696.

The product of its digits is 87480, while the sum is 40.

The square root of 16399543 is about 4049.6349218170. The cubic root of 16399543 is about 254.0644586030.

The spelling of 16399543 in words is "sixteen million, three hundred ninety-nine thousand, five hundred forty-three".