12421728 has 96 divisors (see below), whose sum is σ = 39553920. Its totient is φ = 3761280.

The previous prime is 12421727. The next prime is 12421757. The reversal of 12421728 is 82712421.

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 (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12421727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8851 + ... + 10157.

It is an arithmetic number, because the mean of its divisors is an integer number (412020).

Almost surely, 2^12421728 is an apocalyptic number.

12421728 is a gapful number since it is divisible by the number (18) 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 12421728, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (19776960).

12421728 is an abundant number, since it is smaller than the sum of its proper divisors (27132192).

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

12421728 is a wasteful number, since it uses less digits than its factorization.

12421728 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1337 (or 1323 counting only the distinct ones).

The product of its digits is 1792, while the sum is 27.

The square root of 12421728 is about 3524.4471906953. The cubic root of 12421728 is about 231.5940184769.

12421728 divided by its sum of digits (27) gives a palindrome (460064).

The spelling of 12421728 in words is "twelve million, four hundred twenty-one thousand, seven hundred twenty-eight".