19943340187 has 8 divisors (see below), whose sum is σ = 20467708976. Its totient is φ = 19421724672.

The previous prime is 19943340167. The next prime is 19943340239. The reversal of 19943340187 is 78104334991.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a 21-Lehmer number, since φ(19943340187) divides (19943340187-1)²¹.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19943340187 is a prime.

It is a pancake number, because a pancake can be divided into 19943340187 parts by 199716 straight cuts.

It is a self number, because there is not a number n which added to its sum of digits gives 19943340187.

It is not an unprimeable number, because it can be changed into a prime (19943340127) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 673638 + ... + 702619.

It is an arithmetic number, because the mean of its divisors is an integer number (2558463622).

Almost surely, 2^19943340187 is an apocalyptic number.

19943340187 is a deficient number, since it is larger than the sum of its proper divisors (524368789).

19943340187 is a wasteful number, since it uses less digits than its factorization.

19943340187 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1376637.

The product of its (nonzero) digits is 653184, while the sum is 49.

The spelling of 19943340187 in words is "nineteen billion, nine hundred forty-three million, three hundred forty thousand, one hundred eighty-seven".