12003506721 has 12 divisors (see below), whose sum is σ = 17980561872. Its totient is φ = 8002337652.

The previous prime is 12003506707. The next prime is 12003506773. The reversal of 12003506721 is 12760530021.

It is a happy number.

It is not a de Polignac number, because 12003506721 - 2⁵ = 12003506689 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (12003526721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 24698331 + ... + 24698816.

It is an arithmetic number, because the mean of its divisors is an integer number (1498380156).

Almost surely, 2^12003506721 is an apocalyptic number.

It is an amenable number.

12003506721 is a deficient number, since it is larger than the sum of its proper divisors (5977055151).

12003506721 is an frugal number, since it uses more digits than its factorization.

12003506721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49397162 (or 49397150 counting only the distinct ones).

The product of its (nonzero) digits is 2520, while the sum is 27.

The spelling of 12003506721 in words is "twelve billion, three million, five hundred six thousand, seven hundred twenty-one".