7978813756 has 24 divisors (see below), whose sum is σ = 14107554720. Its totient is φ = 3948120000.

The previous prime is 7978813753. The next prime is 7978813757. The reversal of 7978813756 is 6573188797.

It is a super-2 number, since 2×7978813756² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 7978813694 and 7978813703.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7978813753) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1609081 + ... + 1614031.

It is an arithmetic number, because the mean of its divisors is an integer number (587814780).

Almost surely, 2^7978813756 is an apocalyptic number.

It is an amenable number.

7978813756 is a deficient number, since it is larger than the sum of its proper divisors (6128740964).

7978813756 is a wasteful number, since it uses less digits than its factorization.

7978813756 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9045 (or 9043 counting only the distinct ones).

The product of its digits is 17781120, while the sum is 61.

The square root of 7978813756 is about 89324.2058794815. The cubic root of 7978813756 is about 1998.2329188386.

The spelling of 7978813756 in words is "seven billion, nine hundred seventy-eight million, eight hundred thirteen thousand, seven hundred fifty-six".