12021408 has 144 divisors (see below), whose sum is σ = 40098240. Its totient is φ = 3345408.

The previous prime is 12021403. The next prime is 12021473. The reversal of 12021408 is 80412021.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (12021403) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 135028 + ... + 135116.

It is an arithmetic number, because the mean of its divisors is an integer number (278460).

Almost surely, 2^12021408 is an apocalyptic number.

12021408 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 12021408, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (20049120).

12021408 is an abundant number, since it is smaller than the sum of its proper divisors (28076832).

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

12021408 is a wasteful number, since it uses less digits than its factorization.

12021408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 179 (or 168 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 12021408 is about 3467.1902168759. The cubic root of 12021408 is about 229.0789123107.

Adding to 12021408 its reverse (80412021), we get a palindrome (92433429).

It can be divided in two parts, 120 and 21408, that added together give a triangular number (21528 = T₂₀₇).

The spelling of 12021408 in words is "twelve million, twenty-one thousand, four hundred eight".