19099799987 has 4 divisors (see below), whose sum is σ = 19237208760. Its totient is φ = 18962391216.

The previous prime is 19099799861. The next prime is 19099799993. The reversal of 19099799987 is 78999799091.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 19099799987 - 2¹⁴ = 19099783603 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (19099799087) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 68704178 + ... + 68704455.

It is an arithmetic number, because the mean of its divisors is an integer number (4809302190).

Almost surely, 2^19099799987 is an apocalyptic number.

19099799987 is a deficient number, since it is larger than the sum of its proper divisors (137408773).

19099799987 is a wasteful number, since it uses less digits than its factorization.

19099799987 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137408772.

The product of its (nonzero) digits is 208324872, while the sum is 77.

The spelling of 19099799987 in words is "nineteen billion, ninety-nine million, seven hundred ninety-nine thousand, nine hundred eighty-seven".