21212002112 has 56 divisors (see below), whose sum is σ = 48277272000. Its totient is φ = 9058452480.

The previous prime is 21212002069. The next prime is 21212002139. The reversal of 21212002112 is 21120021212.

It is a tau number, because it is divible by the number of its divisors (56).

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 41639 + ... + 210137.

Almost surely, 2^21212002112 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 21212002112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24138636000).

21212002112 is an abundant number, since it is smaller than the sum of its proper divisors (27065269888).

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

21212002112 is a wasteful number, since it uses less digits than its factorization.

21212002112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168799 (or 168789 counting only the distinct ones).

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

Adding to 21212002112 its reverse (21120021212), we get a palindrome (42332023324).

The spelling of 21212002112 in words is "twenty-one billion, two hundred twelve million, two thousand, one hundred twelve".