7681399856 has 80 divisors (see below), whose sum is σ = 16457696640. Its totient is φ = 3450531840.

The previous prime is 7681399841. The next prime is 7681399871. The reversal of 7681399856 is 6589931867.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (7681399841) and next prime (7681399871).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4851641 + ... + 4853223.

It is an arithmetic number, because the mean of its divisors is an integer number (205721208).

Almost surely, 2^7681399856 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7681399856, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (8228848320).

7681399856 is an abundant number, since it is smaller than the sum of its proper divisors (8776296784).

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

7681399856 is a wasteful number, since it uses less digits than its factorization.

7681399856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2214 (or 2208 counting only the distinct ones).

The product of its digits is 19595520, while the sum is 62.

The square root of 7681399856 is about 87643.5956359619. The cubic root of 7681399856 is about 1973.0895251600.

The spelling of 7681399856 in words is "seven billion, six hundred eighty-one million, three hundred ninety-nine thousand, eight hundred fifty-six".