16819939 has 4 divisors (see below), whose sum is σ = 16856424. Its totient is φ = 16783456.

The previous prime is 16819931. The next prime is 16819961. The reversal of 16819939 is 93991861.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93991861 = 17 ⋅5528933.

It is a cyclic number.

It is not a de Polignac number, because 16819939 - 2³ = 16819931 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16819931) 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, 17542 + ... + 18475.

It is an arithmetic number, because the mean of its divisors is an integer number (4214106).

Almost surely, 2^16819939 is an apocalyptic number.

16819939 is a deficient number, since it is larger than the sum of its proper divisors (36485).

16819939 is an equidigital number, since it uses as much as digits as its factorization.

16819939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36484.

The product of its digits is 104976, while the sum is 46.

The square root of 16819939 is about 4101.2118940625. The cubic root of 16819939 is about 256.2171162245.

The spelling of 16819939 in words is "sixteen million, eight hundred nineteen thousand, nine hundred thirty-nine".