7878998787 has 16 divisors (see below), whose sum is σ = 11524394880. Its totient is φ = 4748470400.

The previous prime is 7878998779. The next prime is 7878998791.

7878998787 is nontrivially palindromic in base 10.

It is a cyclic number.

It is not a de Polignac number, because 7878998787 - 2³ = 7878998779 is a prime.

It is not an unprimeable number, because it can be changed into a prime (7878997787) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 661014 + ... + 672827.

It is an arithmetic number, because the mean of its divisors is an integer number (720274680).

Almost surely, 2^7878998787 is an apocalyptic number.

7878998787 is a deficient number, since it is larger than the sum of its proper divisors (3645396093).

7878998787 is a wasteful number, since it uses less digits than its factorization.

7878998787 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1334034.

The product of its digits is 796594176, while the sum is 78.

The square root of 7878998787 is about 88763.7244993697. The cubic root of 7878998787 is about 1989.8652962195.

The spelling of 7878998787 in words is "seven billion, eight hundred seventy-eight million, nine hundred ninety-eight thousand, seven hundred eighty-seven".