21321120 has 96 divisors (see below), whose sum is σ = 68789952. Its totient is φ = 5548032.

The previous prime is 21321101. The next prime is 21321121. The reversal of 21321120 is 2112312.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a junction number, because it is equal to n+sod(n) for n = 21321096 and 21321105.

It is not an unprimeable number, because it can be changed into a prime (21321121) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20124 + ... + 21156.

It is an arithmetic number, because the mean of its divisors is an integer number (716562).

Almost surely, 2^21321120 is an apocalyptic number.

21321120 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 21321120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34394976).

21321120 is an abundant number, since it is smaller than the sum of its proper divisors (47468832).

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

21321120 is a wasteful number, since it uses less digits than its factorization.

21321120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1094 (or 1086 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 21321120 is about 4617.4798321162. The cubic root of 21321120 is about 277.2915730596.

Adding to 21321120 its reverse (2112312), we get a palindrome (23433432).

The spelling of 21321120 in words is "twenty-one million, three hundred twenty-one thousand, one hundred twenty".