21111110222400 has 504 divisors, whose sum is σ = 84886819958304. Its totient is φ = 5117843865600.

The previous prime is 21111110222399. The next prime is 21111110222483. The reversal of 21111110222400 is 422201111112.

21111110222400 is a `hidden beast` number, since 21 + 1 + 1 + 11 + 10 + 222 + 400 = 666.

It is a super-3 number, since 3×21111110222400³ (a number of 41 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 1808704 + ... + 6744896.

It is an arithmetic number, because the mean of its divisors is an integer number (168426230076).

Almost surely, 2^{21111110222400} is an apocalyptic number.

21111110222400 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 21111110222400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42443409979152).

21111110222400 is an abundant number, since it is smaller than the sum of its proper divisors (63775709735904).

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

21111110222400 is a wasteful number, since it uses less digits than its factorization.

21111110222400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4936241 (or 4936214 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 18.

Adding to 21111110222400 its reverse (422201111112), we get a palindrome (21533311333512).

The spelling of 21111110222400 in words is "twenty-one trillion, one hundred eleven billion, one hundred ten million, two hundred twenty-two thousand, four hundred".