7871770728 has 256 divisors, whose sum is σ = 23601715200. Its totient is φ = 2426112000.

The previous prime is 7871770727. The next prime is 7871770741. The reversal of 7871770728 is 8270771787.

It is a Cunningham number, because it is equal to 88723²-1.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is not an unprimeable number, because it can be changed into a prime (7871770727) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 14550138 + ... + 14550678.

It is an arithmetic number, because the mean of its divisors is an integer number (92194200).

Almost surely, 2^7871770728 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 7871770728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (11800857600).

7871770728 is an abundant number, since it is smaller than the sum of its proper divisors (15729944472).

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

7871770728 is a wasteful number, since it uses less digits than its factorization.

With its successor (7871770729) it forms an eRAP, since the sums of their prime factors are consecutive (681 and 682).

7871770728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 681 (or 671 counting only the distinct ones).

The product of its (nonzero) digits is 2151296, while the sum is 54.

The square root of 7871770728 is about 88722.9999943645. Note that the first 5 decimals coincide. The cubic root of 7871770728 is about 1989.2566205661.

The spelling of 7871770728 in words is "seven billion, eight hundred seventy-one million, seven hundred seventy thousand, seven hundred twenty-eight".