21212012210000 has 100 divisors (see below), whose sum is σ = 51383780052000. Its totient is φ = 8480281776000.

The previous prime is 21212012209991. The next prime is 21212012210017. The reversal of 21212012210000 is 1221021212.

It is a tau number, because it is divible by the number of its divisors (100).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 18225551 + ... + 19354449.

It is an arithmetic number, because the mean of its divisors is an integer number (513837800520).

Almost surely, 2^{21212012210000} is an apocalyptic number.

21212012210000 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 21212012210000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25691890026000).

21212012210000 is an abundant number, since it is smaller than the sum of its proper divisors (30171767842000).

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

21212012210000 is a wasteful number, since it uses less digits than its factorization.

21212012210000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1130806 (or 1130785 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21212012210000 its reverse (1221021212), we get a palindrome (21213233231212).

The spelling of 21212012210000 in words is "twenty-one trillion, two hundred twelve billion, twelve million, two hundred ten thousand".