9972879820 has 24 divisors (see below), whose sum is σ = 20946063600. Its totient is φ = 3988577472.

The previous prime is 9972879797. The next prime is 9972879827. The reversal of 9972879820 is 289782799.

It is not an unprimeable number, because it can be changed into a prime (9972879827) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 123771 + ... + 187789.

It is an arithmetic number, because the mean of its divisors is an integer number (872752650).

Almost surely, 2^9972879820 is an apocalyptic number.

It is an amenable number.

9972879820 is an abundant number, since it is smaller than the sum of its proper divisors (10973183780).

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

9972879820 is a wasteful number, since it uses less digits than its factorization.

9972879820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71817 (or 71815 counting only the distinct ones).

The product of its (nonzero) digits is 9144576, while the sum is 61.

The square root of 9972879820 is about 99864.3070370991. The cubic root of 9972879820 is about 2152.4853048261.

The spelling of 9972879820 in words is "nine billion, nine hundred seventy-two million, eight hundred seventy-nine thousand, eight hundred twenty".