21134247840000 has 675 divisors, whose sum is σ = 78809635982077. Its totient is φ = 5631386112000.

The previous prime is 21134247839927. The next prime is 21134247840007. The reversal of 21134247840000 is 4874243112.

The square root of 21134247840000 is 4597200.

It is a perfect power (a square), and thus also a powerful number.

21134247840000 is a `hidden beast` number, since 2 + 1 + 1 + 3 + 4 + 247 + 8 + 400 + 0 + 0 = 666.

It can be written as a sum of positive squares in 7 ways, for example, as 13165054343424 + 7969193496576 = 3628368^2 + 2822976^2 .

It is a tau number, because it is divible by the number of its divisors (675).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21134247840007) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 74 ways as a sum of consecutive naturals, for example, 16549919362 + ... + 16549920638.

Almost surely, 2^{21134247840000} is an apocalyptic number.

21134247840000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

21134247840000 is the 4597200-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21134247840000

21134247840000 is an abundant number, since it is smaller than the sum of its proper divisors (57675388142077).

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

21134247840000 is an frugal number, since it uses more digits than its factorization.

21134247840000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2602 (or 1287 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 36.

Multiplying 21134247840000 by its sum of digits (36), we get a square (760832922240000 = 27583200²).

21134247840000 divided by its sum of digits (36) gives a square (587062440000 = 766200²).

The spelling of 21134247840000 in words is "twenty-one trillion, one hundred thirty-four billion, two hundred forty-seven million, eight hundred forty thousand".