21444035222400 has 384 divisors, whose sum is σ = 81926290786560. Its totient is φ = 4828336128000.

The previous prime is 21444035222369. The next prime is 21444035222419. The reversal of 21444035222400 is 422253044412.

It is a tau number, because it is divible by the number of its divisors (384).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 2121000 + ... + 6883800.

It is an arithmetic number, because the mean of its divisors is an integer number (213349715590).

Almost surely, 2^{21444035222400} is an apocalyptic number.

21444035222400 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 21444035222400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40963145393280).

21444035222400 is an abundant number, since it is smaller than the sum of its proper divisors (60482255564160).

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

21444035222400 is a wasteful number, since it uses less digits than its factorization.

21444035222400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4762902 (or 4762885 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 33.

Adding to 21444035222400 its reverse (422253044412), we get a palindrome (21866288266812).

The spelling of 21444035222400 in words is "twenty-one trillion, four hundred forty-four billion, thirty-five million, two hundred twenty-two thousand, four hundred".