7878478660 has 24 divisors (see below), whose sum is σ = 17817483096. Its totient is φ = 2908976640.

The previous prime is 7878478609. The next prime is 7878478711. The reversal of 7878478660 is 668748787.

It is an interprime number because it is at equal distance from previous prime (7878478609) and next prime (7878478711).

It can be written as a sum of positive squares in 4 ways, for example, as 1335610116 + 6542868544 = 36546^2 + 80888^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15150661 + ... + 15151180.

It is an arithmetic number, because the mean of its divisors is an integer number (742395129).

Almost surely, 2^7878478660 is an apocalyptic number.

It is an amenable number.

7878478660 is an abundant number, since it is smaller than the sum of its proper divisors (9939004436).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

7878478660 is a wasteful number, since it uses less digits than its factorization.

7878478660 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30301863 (or 30301861 counting only the distinct ones).

The product of its (nonzero) digits is 25288704, while the sum is 61.

The square root of 7878478660 is about 88760.7946111345. The cubic root of 7878478660 is about 1989.8215086998.

The spelling of 7878478660 in words is "seven billion, eight hundred seventy-eight million, four hundred seventy-eight thousand, six hundred sixty".