21540423000 has 128 divisors (see below), whose sum is σ = 67260510720. Its totient is φ = 5739465600.

The previous prime is 21540422989. The next prime is 21540423007. The reversal of 21540423000 is 32404512.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21540423007) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5346987 + ... + 5351013.

It is an arithmetic number, because the mean of its divisors is an integer number (525472740).

Almost surely, 2^21540423000 is an apocalyptic number.

21540423000 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 21540423000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33630255360).

21540423000 is an abundant number, since it is smaller than the sum of its proper divisors (45720087720).

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

21540423000 is a wasteful number, since it uses less digits than its factorization.

21540423000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5834 (or 5820 counting only the distinct ones).

The product of its (nonzero) digits is 960, while the sum is 21.

Adding to 21540423000 its reverse (32404512), we get a palindrome (21572827512).

The spelling of 21540423000 in words is "twenty-one billion, five hundred forty million, four hundred twenty-three thousand".