21012110121200 has 120 divisors (see below), whose sum is σ = 55091160602256. Its totient is φ = 7637946624000.

The previous prime is 21012110121127. The next prime is 21012110121239. The reversal of 21012110121200 is 212101121012.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 11057090 + ... + 12817310.

Almost surely, 2^{21012110121200} is an apocalyptic number.

21012110121200 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 21012110121200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27545580301128).

21012110121200 is an abundant number, since it is smaller than the sum of its proper divisors (34079050481056).

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

21012110121200 is a wasteful number, since it uses less digits than its factorization.

21012110121200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1762963 (or 1762952 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 21012110121200 its reverse (212101121012), we get a palindrome (21224211242212).

The spelling of 21012110121200 in words is "twenty-one trillion, twelve billion, one hundred ten million, one hundred twenty-one thousand, two hundred".