7878778787 has 8 divisors (see below), whose sum is σ = 8596085952. Its totient is φ = 7161647400.

The previous prime is 7878778769. The next prime is 7878778813.

7878778787 is nontrivially palindromic in base 10.

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

It is a cyclic number.

It is not a de Polignac number, because 7878778787 - 2¹⁴ = 7878762403 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7878778487) 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, 60608 + ... + 139394.

It is an arithmetic number, because the mean of its divisors is an integer number (1074510744).

Almost surely, 2^7878778787 is an apocalyptic number.

7878778787 is a deficient number, since it is larger than the sum of its proper divisors (717307165).

7878778787 is a wasteful number, since it uses less digits than its factorization.

7878778787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 87889.

The product of its digits is 481890304, while the sum is 74.

The square root of 7878778787 is about 88762.4852457388. The cubic root of 7878778787 is about 1989.8467754890.

The spelling of 7878778787 in words is "seven billion, eight hundred seventy-eight million, seven hundred seventy-eight thousand, seven hundred eighty-seven".