9987799187 has 2 divisors, whose sum is σ = 9987799188. Its totient is φ = 9987799186.

The previous prime is 9987799153. The next prime is 9987799229. The reversal of 9987799187 is 7819977899.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 9987799187 - 2¹² = 9987795091 is a prime.

It is a super-2 number, since 2×9987799187² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (9987799127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4993899593 + 4993899594.

It is an arithmetic number, because the mean of its divisors is an integer number (4993899594).

Almost surely, 2^9987799187 is an apocalyptic number.

9987799187 is a deficient number, since it is larger than the sum of its proper divisors (1).

9987799187 is an equidigital number, since it uses as much as digits as its factorization.

9987799187 is an evil number, because the sum of its binary digits is even.

The product of its digits is 144027072, while the sum is 74.

The square root of 9987799187 is about 99938.9773161603. The cubic root of 9987799187 is about 2153.5581382879.

The spelling of 9987799187 in words is "nine billion, nine hundred eighty-seven million, seven hundred ninety-nine thousand, one hundred eighty-seven".