21127328 has 48 divisors (see below), whose sum is σ = 44743104. Its totient is φ = 9784320.

The previous prime is 21127321. The next prime is 21127331. The reversal of 21127328 is 82372112.

It is a junction number, because it is equal to n+sod(n) for n = 21127297 and 21127306.

It is not an unprimeable number, because it can be changed into a prime (21127321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38351 + ... + 38897.

It is an arithmetic number, because the mean of its divisors is an integer number (932148).

Almost surely, 2^21127328 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21127328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22371552).

21127328 is an abundant number, since it is smaller than the sum of its proper divisors (23615776).

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

21127328 is a wasteful number, since it uses less digits than its factorization.

21127328 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 645 (or 637 counting only the distinct ones).

The product of its digits is 1344, while the sum is 26.

The square root of 21127328 is about 4596.4473237491. The cubic root of 21127328 is about 276.4488949364.

The spelling of 21127328 in words is "twenty-one million, one hundred twenty-seven thousand, three hundred twenty-eight".