7856471840 has 72 divisors (see below), whose sum is σ = 21591289692. Its totient is φ = 2693644800.

The previous prime is 7856471827. The next prime is 7856471873. The reversal of 7856471840 is 481746587.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 7117284496 + 739187344 = 84364^2 + 27188^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 493211 + ... + 508890.

Almost surely, 2^7856471840 is an apocalyptic number.

7856471840 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

7856471840 is an abundant number, since it is smaller than the sum of its proper divisors (13734817852).

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

7856471840 is a wasteful number, since it uses less digits than its factorization.

7856471840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1002130 (or 1002115 counting only the distinct ones).

The product of its (nonzero) digits is 1505280, while the sum is 50.

The square root of 7856471840 is about 88636.7409148148. The cubic root of 7856471840 is about 1987.9670694803.

The spelling of 7856471840 in words is "seven billion, eight hundred fifty-six million, four hundred seventy-one thousand, eight hundred forty".