20112820 has 96 divisors (see below), whose sum is σ = 53399808. Its totient is φ = 6193152.

The previous prime is 20112817. The next prime is 20112821. The reversal of 20112820 is 2821102.

It is a junction number, because it is equal to n+sod(n) for n = 20112794 and 20112803.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20112821) 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 31 ways as a sum of consecutive naturals, for example, 78132 + ... + 78388.

It is an arithmetic number, because the mean of its divisors is an integer number (556248).

Almost surely, 2^20112820 is an apocalyptic number.

20112820 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 20112820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26699904).

20112820 is an abundant number, since it is smaller than the sum of its proper divisors (33286988).

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

20112820 is a wasteful number, since it uses less digits than its factorization.

20112820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 329 (or 327 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 20112820 is about 4484.7318760434. The cubic root of 20112820 is about 271.9512059244.

Adding to 20112820 its reverse (2821102), we get a palindrome (22933922).

The spelling of 20112820 in words is "twenty million, one hundred twelve thousand, eight hundred twenty".