19689939 has 8 divisors (see below), whose sum is σ = 29170320. Its totient is φ = 13126608.

The previous prime is 19689937. The next prime is 19689959. The reversal of 19689939 is 93998691.

It is not a de Polignac number, because 19689939 - 2¹ = 19689937 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19689931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 364602 + ... + 364655.

It is an arithmetic number, because the mean of its divisors is an integer number (3646290).

Almost surely, 2^19689939 is an apocalyptic number.

19689939 is a deficient number, since it is larger than the sum of its proper divisors (9480381).

19689939 is an equidigital number, since it uses as much as digits as its factorization.

19689939 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 729266 (or 729260 counting only the distinct ones).

The product of its digits is 944784, while the sum is 54.

The square root of 19689939 is about 4437.3346729766. The cubic root of 19689939 is about 270.0317246673.

The spelling of 19689939 in words is "nineteen million, six hundred eighty-nine thousand, nine hundred thirty-nine".