21885120000 has 800 divisors, whose sum is σ = 86288004000. Its totient is φ = 5455872000.

The previous prime is 21885119989. The next prime is 21885120043. The reversal of 21885120000 is 2158812.

It is a tau number, because it is divible by the number of its divisors (800).

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 146879926 + ... + 146880074.

It is an arithmetic number, because the mean of its divisors is an integer number (107860005).

Almost surely, 2^21885120000 is an apocalyptic number.

21885120000 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 21885120000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (43144002000).

21885120000 is an abundant number, since it is smaller than the sum of its proper divisors (64402884000).

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

21885120000 is an equidigital number, since it uses as much as digits as its factorization.

21885120000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 213 (or 176 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 27.

Adding to 21885120000 its reverse (2158812), we get a palindrome (21887278812).

The spelling of 21885120000 in words is "twenty-one billion, eight hundred eighty-five million, one hundred twenty thousand".