21111110221200 has 120 divisors (see below), whose sum is σ = 68112441045600. Its totient is φ = 5589128417280.

The previous prime is 21111110221193. The next prime is 21111110221207. The reversal of 21111110221200 is 212201111112.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (21111110221193) and next prime (21111110221207).

It is a tau number, because it is divible by the number of its divisors (120).

It is a super-3 number, since 3×21111110221200³ (a number of 41 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21111110221200.

It is not an unprimeable number, because it can be changed into a prime (21111110221207) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 63115905 + ... + 63449504.

It is an arithmetic number, because the mean of its divisors is an integer number (567603675380).

Almost surely, 2^{21111110221200} is an apocalyptic number.

21111110221200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21111110221200 is an abundant number, since it is smaller than the sum of its proper divisors (47001330824400).

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

21111110221200 is a wasteful number, since it uses less digits than its factorization.

21111110221200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 126565569 (or 126565558 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 21111110221200 its reverse (212201111112), we get a palindrome (21323311332312).

The spelling of 21111110221200 in words is "twenty-one trillion, one hundred eleven billion, one hundred ten million, two hundred twenty-one thousand, two hundred".