21111011200 has 96 divisors (see below), whose sum is σ = 52196715000. Its totient is φ = 8436971520.

The previous prime is 21111011189. The next prime is 21111011231. The reversal of 21111011200 is 211011112.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4954671 + ... + 4958929.

Almost surely, 2^21111011200 is an apocalyptic number.

21111011200 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 21111011200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26098357500).

21111011200 is an abundant number, since it is smaller than the sum of its proper divisors (31085703800).

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

21111011200 is a wasteful number, since it uses less digits than its factorization.

21111011200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5832 (or 5815 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 10.

Adding to 21111011200 its reverse (211011112), we get a palindrome (21322022312).

The spelling of 21111011200 in words is "twenty-one billion, one hundred eleven million, eleven thousand, two hundred".