20533212 has 72 divisors (see below), whose sum is σ = 62820576. Its totient is φ = 5520384.

The previous prime is 20533159. The next prime is 20533213. The reversal of 20533212 is 21233502.

It is a super-2 number, since 2×20533212² = 843225590073888, which contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20533213) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1888 + ... + 6680.

It is an arithmetic number, because the mean of its divisors is an integer number (872508).

Almost surely, 2^20533212 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 20533212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31410288).

20533212 is an abundant number, since it is smaller than the sum of its proper divisors (42287364).

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

20533212 is a wasteful number, since it uses less digits than its factorization.

20533212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4827 (or 4822 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 18.

The square root of 20533212 is about 4531.3587366264. The cubic root of 20533212 is about 273.8329028950.

Adding to 20533212 its reverse (21233502), we get a palindrome (41766714).

The spelling of 20533212 in words is "twenty million, five hundred thirty-three thousand, two hundred twelve".