20984820 has 48 divisors (see below), whose sum is σ = 59875200. Its totient is φ = 5489536.

The previous prime is 20984819. The next prime is 20984827. The reversal of 20984820 is 2848902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20984827) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 120 + ... + 6479.

It is an arithmetic number, because the mean of its divisors is an integer number (1247400).

Almost surely, 2^20984820 is an apocalyptic number.

20984820 is a gapful number since it is divisible by the number (20) 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 20984820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29937600).

20984820 is an abundant number, since it is smaller than the sum of its proper divisors (38890380).

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

20984820 is a wasteful number, since it uses less digits than its factorization.

20984820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6664 (or 6662 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 33.

The square root of 20984820 is about 4580.9191217484. The cubic root of 20984820 is about 275.8259246790.

The spelling of 20984820 in words is "twenty million, nine hundred eighty-four thousand, eight hundred twenty".