12003021 has 6 divisors (see below), whose sum is σ = 17337710. Its totient is φ = 8002008.

The previous prime is 12003011. The next prime is 12003073. The reversal of 12003021 is 12030021.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 10634121 + 1368900 = 3261^2 + 1170^2 .

It is not a de Polignac number, because 12003021 - 2⁵ = 12002989 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 1333669 = 12003021 / (1 + 2 + 0 + 0 + 3 + 0 + 2 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12002994 and 12003012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12003011) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 666826 + ... + 666843.

Almost surely, 2^12003021 is an apocalyptic number.

It is an amenable number.

12003021 is a deficient number, since it is larger than the sum of its proper divisors (5334689).

12003021 is a wasteful number, since it uses less digits than its factorization.

12003021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1333675 (or 1333672 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 12003021 is about 3464.5376314885. The cubic root of 12003021 is about 228.9620590194.

Adding to 12003021 its reverse (12030021), we get a palindrome (24033042).

Subtracting 12003021 from its reverse (12030021), we obtain a cube (27000 = 30³).

The spelling of 12003021 in words is "twelve million, three thousand, twenty-one".