20979792 has 60 divisors (see below), whose sum is σ = 59410260. Its totient is φ = 6910464.

The previous prime is 20979779. The next prime is 20979799. The reversal of 20979792 is 29797902.

It can be written as a sum of positive squares in 2 ways, for example, as 2005056 + 18974736 = 1416^2 + 4356^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20979799) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11998 + ... + 13634.

It is an arithmetic number, because the mean of its divisors is an integer number (990171).

Almost surely, 2^20979792 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 20979792, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29705130).

20979792 is an abundant number, since it is smaller than the sum of its proper divisors (38430468).

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

20979792 is a wasteful number, since it uses less digits than its factorization.

20979792 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1740 (or 1731 counting only the distinct ones).

The product of its (nonzero) digits is 142884, while the sum is 45.

The square root of 20979792 is about 4580.3702907079. The cubic root of 20979792 is about 275.8038934595.

The spelling of 20979792 in words is "twenty million, nine hundred seventy-nine thousand, seven hundred ninety-two".