20281212 has 96 divisors (see below), whose sum is σ = 60838400. Its totient is φ = 5723136.

The previous prime is 20281211. The next prime is 20281229. The reversal of 20281212 is 21218202.

It is a happy number.

It is a super-2 number, since 2×20281212² = 822655120377888, which contains 22 as substring.

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

It is a plaindrome in base 16.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20281211) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 104988 + ... + 105180.

Almost surely, 2^20281212 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 20281212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (30419200).

20281212 is an abundant number, since it is smaller than the sum of its proper divisors (40557188).

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

20281212 is a wasteful number, since it uses less digits than its factorization.

20281212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352 (or 344 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 20281212 is about 4503.4666646929. The cubic root of 20281212 is about 272.7080564642.

Adding to 20281212 its reverse (21218202), we get a palindrome (41499414).

It can be divided in two parts, 2028 and 1212, that added together give a triangular number (3240 = T₈₀).

The spelling of 20281212 in words is "twenty million, two hundred eighty-one thousand, two hundred twelve".