19689781899 has 4 divisors (see below), whose sum is σ = 26253042536. Its totient is φ = 13126521264.

The previous prime is 19689781861. The next prime is 19689781901. The reversal of 19689781899 is 99818798691.

It is a semiprime because it is the product of two primes.

It is a de Polignac number, because none of the positive numbers 2^k-19689781899 is a prime.

It is a super-2 number, since 2×19689781899² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19689781899.

It is not an unprimeable number, because it can be changed into a prime (19689781499) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3281630314 + ... + 3281630319.

It is an arithmetic number, because the mean of its divisors is an integer number (6563260634).

Almost surely, 2^19689781899 is an apocalyptic number.

19689781899 is a deficient number, since it is larger than the sum of its proper divisors (6563260637).

19689781899 is an equidigital number, since it uses as much as digits as its factorization.

19689781899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6563260636.

The product of its digits is 141087744, while the sum is 75.

The spelling of 19689781899 in words is "nineteen billion, six hundred eighty-nine million, seven hundred eighty-one thousand, eight hundred ninety-nine".