21000200111100 has 288 divisors, whose sum is σ = 77200577180160. Its totient is φ = 4797290603520.

The previous prime is 21000200111039. The next prime is 21000200111123. The reversal of 21000200111100 is 111100200012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 32700292 + ... + 33336308.

Almost surely, 2^{21000200111100} is an apocalyptic number.

21000200111100 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 21000200111100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38600288590080).

21000200111100 is an abundant number, since it is smaller than the sum of its proper divisors (56200377069060).

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

21000200111100 is a wasteful number, since it uses less digits than its factorization.

21000200111100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 637794 (or 637781 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 9.

Adding to 21000200111100 its reverse (111100200012), we get a palindrome (21111300311112).

The spelling of 21000200111100 in words is "twenty-one trillion, two hundred million, one hundred eleven thousand, one hundred".