7994817920 has 128 divisors (see below), whose sum is σ = 19715041440. Its totient is φ = 3097903104.

The previous prime is 7994817907. The next prime is 7994817931. The reversal of 7994817920 is 297184997.

It is a tau number, because it is divible by the number of its divisors (128).

It is a super-2 number, since 2×7994817920² (a number of 21 digits) contains 22 as substring.

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 a congruent number.

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, 6700844 + ... + 6702036.

Almost surely, 2^7994817920 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 7994817920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (9857520720).

7994817920 is an abundant number, since it is smaller than the sum of its proper divisors (11720223520).

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

7994817920 is a wasteful number, since it uses less digits than its factorization.

7994817920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1532 (or 1520 counting only the distinct ones).

The product of its (nonzero) digits is 2286144, while the sum is 56.

The square root of 7994817920 is about 89413.7456994169. The cubic root of 7994817920 is about 1999.5680667235.

The spelling of 7994817920 in words is "seven billion, nine hundred ninety-four million, eight hundred seventeen thousand, nine hundred twenty".