7979797980 has 432 divisors, whose sum is σ = 30936263904. Its totient is φ = 1646346240.

The previous prime is 7979797949. The next prime is 7979797999. The reversal of 7979797980 is 897979797.

It is a super-2 number, since 2×7979797980² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 7979797899 and 7979797908.

It is a congruent number.

It is an unprimeable number.

It is a Kaprekar number, because its square (63677175801612080400) can be partitioned into two parts whose sum is 7979797980.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 22605484 + ... + 22605836.

It is an arithmetic number, because the mean of its divisors is an integer number (71611722).

Almost surely, 2^7979797980 is an apocalyptic number.

7979797980 is a gapful number since it is divisible by the number (70) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 7979797980, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15468131952).

7979797980 is an abundant number, since it is smaller than the sum of its proper divisors (22956465924).

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

7979797980 is a wasteful number, since it uses less digits than its factorization.

7979797980 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 626 (or 614 counting only the distinct ones).

The product of its (nonzero) digits is 126023688, while the sum is 72.

The square root of 7979797980 is about 89329.7149889106. The cubic root of 7979797980 is about 1998.3150792530.

The spelling of 7979797980 in words is "seven billion, nine hundred seventy-nine million, seven hundred ninety-seven thousand, nine hundred eighty".