21213012000000 has 252 divisors, whose sum is σ = 70571071053728. Its totient is φ = 5656800000000.

The previous prime is 21213011999969. The next prime is 21213012000007. The reversal of 21213012000000 is 21031212.

It is a super-2 number, since 2×21213012000000² (a number of 27 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a self number, because there is not a number n which added to its sum of digits gives 21213012000000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21213012000007) by changing a digit.

It is a polite number, since it can be written in 27 ways as a sum of consecutive naturals, for example, 11116125 + ... + 12883875.

Almost surely, 2^{21213012000000} is an apocalyptic number.

21213012000000 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 21213012000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35285535526864).

21213012000000 is an abundant number, since it is smaller than the sum of its proper divisors (49358059053728).

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

21213012000000 is an frugal number, since it uses more digits than its factorization.

21213012000000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1767800 (or 1767761 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

Adding to 21213012000000 its reverse (21031212), we get a palindrome (21213033031212).

The spelling of 21213012000000 in words is "twenty-one trillion, two hundred thirteen billion, twelve million", and thus it is an aban number.