21138336000 has 432 divisors, whose sum is σ = 80085882240. Its totient is φ = 5338828800.

The previous prime is 21138335971. The next prime is 21138336007. The reversal of 21138336000 is 63383112.

It is a happy number.

21138336000 is a `hidden beast` number, since 21 + 1 + 3 + 8 + 33 + 600 + 0 = 666.

It is not an unprimeable number, because it can be changed into a prime (21138336007) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 5470069 + ... + 5473931.

Almost surely, 2^21138336000 is an apocalyptic number.

21138336000 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 21138336000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40042941120).

21138336000 is an abundant number, since it is smaller than the sum of its proper divisors (58947546240).

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

21138336000 is a wasteful number, since it uses less digits than its factorization.

21138336000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3919 (or 3892 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 27.

The spelling of 21138336000 in words is "twenty-one billion, one hundred thirty-eight million, three hundred thirty-six thousand".