21411344400 has 120 divisors (see below), whose sum is σ = 68698799424. Its totient is φ = 5700441600.

The previous prime is 21411344389. The next prime is 21411344429. The reversal of 21411344400 is 444311412.

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

It is a super-2 number, since 2×21411344400² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 743062 + ... + 771338.

Almost surely, 2^21411344400 is an apocalyptic number.

21411344400 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 21411344400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34349399712).

21411344400 is an abundant number, since it is smaller than the sum of its proper divisors (47287455024).

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

21411344400 is a wasteful number, since it uses less digits than its factorization.

21411344400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28929 (or 28918 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 24.

Adding to 21411344400 its reverse (444311412), we get a palindrome (21855655812).

The spelling of 21411344400 in words is "twenty-one billion, four hundred eleven million, three hundred forty-four thousand, four hundred".