21213543326612 has 96 divisors (see below), whose sum is σ = 48105744449280. Its totient is φ = 7948781475840.

The previous prime is 21213543326581. The next prime is 21213543326639. The reversal of 21213543326612 is 21662334531212.

It is a self number, because there is not a number n which added to its sum of digits gives 21213543326612.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 32325578 + ... + 32975294.

It is an arithmetic number, because the mean of its divisors is an integer number (501101504680).

Almost surely, 2^{21213543326612} 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 21213543326612, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24052872224640).

21213543326612 is an abundant number, since it is smaller than the sum of its proper divisors (26892201122668).

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

21213543326612 is a wasteful number, since it uses less digits than its factorization.

21213543326612 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 654481 (or 654479 counting only the distinct ones).

The product of its digits is 311040, while the sum is 41.

Adding to 21213543326612 its reverse (21662334531212), we get a palindrome (42875877857824).

The spelling of 21213543326612 in words is "twenty-one trillion, two hundred thirteen billion, five hundred forty-three million, three hundred twenty-six thousand, six hundred twelve".