7855878440 has 32 divisors (see below), whose sum is σ = 18285237000. Its totient is φ = 3033993984.

The previous prime is 7855878409. The next prime is 7855878461. The reversal of 7855878440 is 448785587.

It can be written as a sum of positive squares in 4 ways, for example, as 5867253604 + 1988624836 = 76598^2 + 44594^2 .

It is a Smith number, since the sum of its digits (56) coincides with the sum of the digits of its prime factors.

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, 3384995 + ... + 3387314.

Almost surely, 2^7855878440 is an apocalyptic number.

It is an amenable number.

7855878440 is an abundant number, since it is smaller than the sum of its proper divisors (10429358560).

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

7855878440 is a wasteful number, since it uses less digits than its factorization.

7855878440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6772349 (or 6772345 counting only the distinct ones).

The product of its (nonzero) digits is 10035200, while the sum is 56.

The square root of 7855878440 is about 88633.3934812382. The cubic root of 7855878440 is about 1987.9170177784.

The spelling of 7855878440 in words is "seven billion, eight hundred fifty-five million, eight hundred seventy-eight thousand, four hundred forty".