19887946195 has 24 divisors (see below), whose sum is σ = 25875318672. Its totient is φ = 14667868800.

The previous prime is 19887946193. The next prime is 19887946207. The reversal of 19887946195 is 59164978891.

It is not a de Polignac number, because 19887946195 - 2¹ = 19887946193 is a prime.

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 19887946195.

It is not an unprimeable number, because it can be changed into a prime (19887946193) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 670785 + ... + 699805.

It is an arithmetic number, because the mean of its divisors is an integer number (1078138278).

Almost surely, 2^19887946195 is an apocalyptic number.

19887946195 is a deficient number, since it is larger than the sum of its proper divisors (5987372477).

19887946195 is a wasteful number, since it uses less digits than its factorization.

19887946195 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29863 (or 29850 counting only the distinct ones).

The product of its digits is 39191040, while the sum is 67.

The spelling of 19887946195 in words is "nineteen billion, eight hundred eighty-seven million, nine hundred forty-six thousand, one hundred ninety-five".