7981779020 has 12 divisors (see below), whose sum is σ = 16761735984. Its totient is φ = 3192711600.

The previous prime is 7981778977. The next prime is 7981779053. The reversal of 7981779020 is 209771897.

It is a super-2 number, since 2×7981779020² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 7981779020.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 199544456 + ... + 199544495.

It is an arithmetic number, because the mean of its divisors is an integer number (1396811332).

Almost surely, 2^7981779020 is an apocalyptic number.

It is an amenable number.

7981779020 is an abundant number, since it is smaller than the sum of its proper divisors (8779956964).

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

7981779020 is a wasteful number, since it uses less digits than its factorization.

7981779020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 399088960 (or 399088958 counting only the distinct ones).

The product of its (nonzero) digits is 444528, while the sum is 50.

The square root of 7981779020 is about 89340.8026603746. The cubic root of 7981779020 is about 1998.4804307470.

The spelling of 7981779020 in words is "seven billion, nine hundred eighty-one million, seven hundred seventy-nine thousand, twenty".