21268480 has 96 divisors (see below), whose sum is σ = 53464320. Its totient is φ = 8110080.

The previous prime is 21268469. The next prime is 21268493. The reversal of 21268480 is 8486212.

It is a Harshad number since it is a multiple of its sum of digits (31).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (5) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 317407 + ... + 317473.

It is an arithmetic number, because the mean of its divisors is an integer number (556920).

Almost surely, 2^21268480 is an apocalyptic number.

21268480 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 21268480, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26732160).

21268480 is an abundant number, since it is smaller than the sum of its proper divisors (32195840).

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

21268480 is an equidigital number, since it uses as much as digits as its factorization.

21268480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125 (or 105 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 31.

The square root of 21268480 is about 4611.7762304778. The cubic root of 21268480 is about 277.0631820321.

The spelling of 21268480 in words is "twenty-one million, two hundred sixty-eight thousand, four hundred eighty".