21194784000 has 1440 divisors, whose sum is σ = 92366610336. Its totient is φ = 4777574400.

The previous prime is 21194783999. The next prime is 21194784043. The reversal of 21194784000 is 48749112.

It can be written as a sum of positive squares in 16 ways, for example, as 11293737984 + 9901046016 = 106272^2 + 99504^2 .

It is a tau number, because it is divible by the number of its divisors (1440).

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 159 ways as a sum of consecutive naturals, for example, 572831982 + ... + 572832018.

Almost surely, 2^21194784000 is an apocalyptic number.

21194784000 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 21194784000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (46183305168).

21194784000 is an abundant number, since it is smaller than the sum of its proper divisors (71171826336).

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

21194784000 is a wasteful number, since it uses less digits than its factorization.

21194784000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110 (or 77 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The spelling of 21194784000 in words is "twenty-one billion, one hundred ninety-four million, seven hundred eighty-four thousand".