20818128 has 80 divisors (see below), whose sum is σ = 56960640. Its totient is φ = 6538752.

The previous prime is 20818121. The next prime is 20818139. The reversal of 20818128 is 82181802.

It is a junction number, because it is equal to n+sod(n) for n = 20818095 and 20818104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20818121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 120250 + ... + 120422.

It is an arithmetic number, because the mean of its divisors is an integer number (712008).

Almost surely, 2^20818128 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 20818128, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28480320).

20818128 is an abundant number, since it is smaller than the sum of its proper divisors (36142512).

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

20818128 is a wasteful number, since it uses less digits than its factorization.

20818128 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 316 (or 310 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 30.

The square root of 20818128 is about 4562.6886810301. The cubic root of 20818128 is about 275.0936452425.

It can be divided in two parts, 2081812 and 8, that added together give a triangular number (2081820 = T₂₀₄₀).

The spelling of 20818128 in words is "twenty million, eight hundred eighteen thousand, one hundred twenty-eight".