21254212 has 48 divisors (see below), whose sum is σ = 44154880. Its totient is φ = 8763552.

The previous prime is 21254183. The next prime is 21254213. The reversal of 21254212 is 21245212.

Its product of digits (320) is a multiple of the sum of its prime factors (320).

It is a self number, because there is not a number n which added to its sum of digits gives 21254212.

It is not an unprimeable number, because it can be changed into a prime (21254213) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 152839 + ... + 152977.

Almost surely, 2^21254212 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 21254212, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22077440).

21254212 is an abundant number, since it is smaller than the sum of its proper divisors (22900668).

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

21254212 is a wasteful number, since it uses less digits than its factorization.

21254212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 320 (or 318 counting only the distinct ones).

The product of its digits is 320, while the sum is 19.

The square root of 21254212 is about 4610.2290615543. The cubic root of 21254212 is about 277.0012120527.

Adding to 21254212 its reverse (21245212), we get a palindrome (42499424).

The spelling of 21254212 in words is "twenty-one million, two hundred fifty-four thousand, two hundred twelve".