21110001200 has 120 divisors (see below), whose sum is σ = 51342262992. Its totient is φ = 8340520960.

The previous prime is 21110001181. The next prime is 21110001287. The reversal of 21110001200 is 210001112.

It is a Harshad number since it is a multiple of its sum of digits (8).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12438752 + ... + 12440448.

Almost surely, 2^21110001200 is an apocalyptic number.

21110001200 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 21110001200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25671131496).

21110001200 is an abundant number, since it is smaller than the sum of its proper divisors (30232261792).

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

21110001200 is a wasteful number, since it uses less digits than its factorization.

21110001200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2079 (or 2068 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 8.

Adding to 21110001200 its reverse (210001112), we get a palindrome (21320002312).

The spelling of 21110001200 in words is "twenty-one billion, one hundred ten million, one thousand, two hundred".