21213212000 has 192 divisors, whose sum is σ = 55566254016. Its totient is φ = 7931289600.

The previous prime is 21213211997. The next prime is 21213212003. The reversal of 21213212000 is 21231212.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21213211997) and next prime (21213212003).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21213212003) 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, 10675007 + ... + 10676993.

It is an arithmetic number, because the mean of its divisors is an integer number (289407573).

Almost surely, 2^21213212000 is an apocalyptic number.

21213212000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21213212000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27783127008).

21213212000 is an abundant number, since it is smaller than the sum of its proper divisors (34353042016).

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

21213212000 is a wasteful number, since it uses less digits than its factorization.

21213212000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2186 (or 2168 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21213212000 its reverse (21231212), we get a palindrome (21234443212).

The spelling of 21213212000 in words is "twenty-one billion, two hundred thirteen million, two hundred twelve thousand".