21200012112 has 80 divisors (see below), whose sum is σ = 58344390720. Its totient is φ = 6610139136.

The previous prime is 21200012107. The next prime is 21200012131. The reversal of 21200012112 is 21121000212.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 53314 + ... + 212702.

It is an arithmetic number, because the mean of its divisors is an integer number (729304884).

Almost surely, 2^21200012112 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 21200012112, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29172195360).

21200012112 is an abundant number, since it is smaller than the sum of its proper divisors (37144378608).

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

21200012112 is a wasteful number, since it uses less digits than its factorization.

21200012112 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159580 (or 159574 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21200012112 its reverse (21121000212), we get a palindrome (42321012324).

The spelling of 21200012112 in words is "twenty-one billion, two hundred million, twelve thousand, one hundred twelve".