19855039 has 4 divisors (see below), whose sum is σ = 19956024. Its totient is φ = 19754056.

The previous prime is 19855021. The next prime is 19855061. The reversal of 19855039 is 93055891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93055891 = 991 ⋅93901.

It is a cyclic number.

It is not a de Polignac number, because 19855039 - 2⁵ = 19855007 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19854992 and 19855010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19855139) 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, 50197 + ... + 50590.

It is an arithmetic number, because the mean of its divisors is an integer number (4989006).

Almost surely, 2^19855039 is an apocalyptic number.

19855039 is a deficient number, since it is larger than the sum of its proper divisors (100985).

19855039 is a wasteful number, since it uses less digits than its factorization.

19855039 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 100984.

The product of its (nonzero) digits is 48600, while the sum is 40.

The square root of 19855039 is about 4455.8993480553. The cubic root of 19855039 is about 270.7843629856.

The spelling of 19855039 in words is "nineteen million, eight hundred fifty-five thousand, thirty-nine".