19885439 has 4 divisors (see below), whose sum is σ = 22726224. Its totient is φ = 17044656.

The previous prime is 19885433. The next prime is 19885447. The reversal of 19885439 is 93458891.

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 19885439 - 2⁴ = 19885423 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 19885393 and 19885402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19885433) 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, 1420382 + ... + 1420395.

It is an arithmetic number, because the mean of its divisors is an integer number (5681556).

Almost surely, 2^19885439 is an apocalyptic number.

19885439 is a deficient number, since it is larger than the sum of its proper divisors (2840785).

19885439 is an equidigital number, since it uses as much as digits as its factorization.

19885439 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2840784.

The product of its digits is 311040, while the sum is 47.

The square root of 19885439 is about 4459.3092514424. The cubic root of 19885439 is about 270.9224915979.

The spelling of 19885439 in words is "nineteen million, eight hundred eighty-five thousand, four hundred thirty-nine".