21281831120 has 80 divisors (see below), whose sum is σ = 54216762048. Its totient is φ = 7704683520.

The previous prime is 21281831119. The next prime is 21281831141. The reversal of 21281831120 is 2113818212.

It is a tau number, because it is divible by the number of its divisors (80).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 146492 + ... + 253028.

Almost surely, 2^21281831120 is an apocalyptic number.

21281831120 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 21281831120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (27108381024).

21281831120 is an abundant number, since it is smaller than the sum of its proper divisors (32934930928).

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

21281831120 is a wasteful number, since it uses less digits than its factorization.

21281831120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 106788 (or 106782 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 29.

The spelling of 21281831120 in words is "twenty-one billion, two hundred eighty-one million, eight hundred thirty-one thousand, one hundred twenty".