20205612 has 120 divisors (see below), whose sum is σ = 61797120. Its totient is φ = 5637600.

The previous prime is 20205611. The next prime is 20205617. The reversal of 20205612 is 21650202.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (20205611) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 133737 + ... + 133887.

It is an arithmetic number, because the mean of its divisors is an integer number (514976).

Almost surely, 2^20205612 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 20205612, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30898560).

20205612 is an abundant number, since it is smaller than the sum of its proper divisors (41591508).

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

20205612 is a wasteful number, since it uses less digits than its factorization.

20205612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 233 (or 222 counting only the distinct ones).

The product of its (nonzero) digits is 240, while the sum is 18.

The square root of 20205612 is about 4495.0652942977. The cubic root of 20205612 is about 272.3687868134.

Adding to 20205612 its reverse (21650202), we get a palindrome (41855814).

The spelling of 20205612 in words is "twenty million, two hundred five thousand, six hundred twelve".