20979399168 has 960 divisors, whose sum is σ = 82577214720. Its totient is φ = 5159780352.

The previous prime is 20979399167. The next prime is 20979399169. The reversal of 20979399168 is 86199397902.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20979399167) and next prime (20979399169).

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20979399167) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 192471498 + ... + 192471606.

It is an arithmetic number, because the mean of its divisors is an integer number (86017932).

Almost surely, 2^20979399168 is an apocalyptic number.

20979399168 is a gapful number since it is divisible by the number (28) 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 20979399168, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41288607360).

20979399168 is an abundant number, since it is smaller than the sum of its proper divisors (61597815552).

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

20979399168 is a wasteful number, since it uses less digits than its factorization.

20979399168 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179 (or 151 counting only the distinct ones).

The product of its (nonzero) digits is 13226976, while the sum is 63.

The spelling of 20979399168 in words is "twenty billion, nine hundred seventy-nine million, three hundred ninety-nine thousand, one hundred sixty-eight".