19980009 has 24 divisors (see below), whose sum is σ = 33388992. Its totient is φ = 11276640.

The previous prime is 19979987. The next prime is 19980019. The reversal of 19980009 is 90008991.

It is not a de Polignac number, because 19980009 - 2⁹ = 19979497 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19980019) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 3319 + ... + 7139.

It is an arithmetic number, because the mean of its divisors is an integer number (1391208).

Almost surely, 2^19980009 is an apocalyptic number.

It is an amenable number.

19980009 is a deficient number, since it is larger than the sum of its proper divisors (13408983).

19980009 is a wasteful number, since it uses less digits than its factorization.

19980009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3917 (or 3914 counting only the distinct ones).

The product of its (nonzero) digits is 5832, while the sum is 36.

The square root of 19980009 is about 4469.9003344594. The cubic root of 19980009 is about 271.3512916387.

It can be divided in two parts, 199 and 80009, that added together give a palindrome (80208).

The spelling of 19980009 in words is "nineteen million, nine hundred eighty thousand, nine".