21836400000 has 384 divisors, whose sum is σ = 74965201920. Its totient is φ = 5625600000.

The previous prime is 21836399999. The next prime is 21836400011. The reversal of 21836400000 is 463812.

It is a happy number.

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

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

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, 37199707 + ... + 37200293.

It is an arithmetic number, because the mean of its divisors is an integer number (195221880).

Almost surely, 2^21836400000 is an apocalyptic number.

21836400000 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 21836400000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (37482600960).

21836400000 is an abundant number, since it is smaller than the sum of its proper divisors (53128801920).

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

21836400000 is an frugal number, since it uses more digits than its factorization.

21836400000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660 (or 628 counting only the distinct ones).

The product of its (nonzero) digits is 1152, while the sum is 24.

Adding to 21836400000 its reverse (463812), we get a palindrome (21836863812).

The spelling of 21836400000 in words is "twenty-one billion, eight hundred thirty-six million, four hundred thousand".