21000210110400 has 168 divisors, whose sum is σ = 68903774003200. Its totient is φ = 5599602109440.

The previous prime is 21000210110263. The next prime is 21000210110401. The reversal of 21000210110400 is 401101200012.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21000210110401) 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, 61264287 + ... + 61606113.

Almost surely, 2^{21000210110400} is an apocalyptic number.

21000210110400 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 21000210110400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34451887001600).

21000210110400 is an abundant number, since it is smaller than the sum of its proper divisors (47903563892800).

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

21000210110400 is a wasteful number, since it uses less digits than its factorization.

21000210110400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354651 (or 354636 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 21000210110400 its reverse (401101200012), we get a palindrome (21401311310412).

The spelling of 21000210110400 in words is "twenty-one trillion, two hundred ten million, one hundred ten thousand, four hundred".