12721044 has 48 divisors (see below), whose sum is σ = 34848128. Its totient is φ = 3535488.

The previous prime is 12721043. The next prime is 12721087. The reversal of 12721044 is 44012721.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 12721044.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12721043) 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, 1062 + ... + 5154.

Almost surely, 2^12721044 is an apocalyptic number.

12721044 is a gapful number since it is divisible by the number (14) 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 12721044, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (17424064).

12721044 is an abundant number, since it is smaller than the sum of its proper divisors (22127084).

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

12721044 is a wasteful number, since it uses less digits than its factorization.

12721044 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4144 (or 4142 counting only the distinct ones).

The product of its (nonzero) digits is 448, while the sum is 21.

The square root of 12721044 is about 3566.6572585546. The cubic root of 12721044 is about 233.4394501449.

Adding to 12721044 its reverse (44012721), we get a palindrome (56733765).

The spelling of 12721044 in words is "twelve million, seven hundred twenty-one thousand, forty-four".