19871663979 has 8 divisors (see below), whose sum is σ = 26513569792. Its totient is φ = 13238767080.

The previous prime is 19871663951. The next prime is 19871664041. The reversal of 19871663979 is 97936617891.

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

It is not a de Polignac number, because 19871663979 - 2¹² = 19871659883 is a prime.

It is a super-2 number, since 2×19871663979² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19871463979) 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, 2247079 + ... + 2255904.

It is an arithmetic number, because the mean of its divisors is an integer number (3314196224).

Almost surely, 2^19871663979 is an apocalyptic number.

19871663979 is a deficient number, since it is larger than the sum of its proper divisors (6641905813).

19871663979 is a wasteful number, since it uses less digits than its factorization.

19871663979 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4504457.

The product of its digits is 30862944, while the sum is 66.

The spelling of 19871663979 in words is "nineteen billion, eight hundred seventy-one million, six hundred sixty-three thousand, nine hundred seventy-nine".