19868889 has 16 divisors (see below), whose sum is σ = 28642880. Its totient is φ = 12208320.

The previous prime is 19868879. The next prime is 19868897. The reversal of 19868889 is 98886891.

It is not a de Polignac number, because 19868889 - 2⁸ = 19868633 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is not an unprimeable number, because it can be changed into a prime (19868819) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2602 + ... + 6819.

It is an arithmetic number, because the mean of its divisors is an integer number (1790180).

Almost surely, 2^19868889 is an apocalyptic number.

19868889 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

19868889 is a deficient number, since it is larger than the sum of its proper divisors (8773991).

19868889 is a wasteful number, since it uses less digits than its factorization.

19868889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9480.

The product of its digits is 1990656, while the sum is 57.

The square root of 19868889 is about 4457.4531966135. The cubic root of 19868889 is about 270.8473107632.

The spelling of 19868889 in words is "nineteen million, eight hundred sixty-eight thousand, eight hundred eighty-nine".