12051721 has 12 divisors (see below), whose sum is σ = 13389376. Its totient is φ = 10838520.

The previous prime is 12051679. The next prime is 12051727. The reversal of 12051721 is 12715021.

12051721 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 12051721 - 2⁹ = 12051209 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12051727) 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 11 ways as a sum of consecutive naturals, for example, 11980 + ... + 12946.

Almost surely, 2^12051721 is an apocalyptic number.

12051721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

12051721 is a deficient number, since it is larger than the sum of its proper divisors (1337655).

12051721 is a wasteful number, since it uses less digits than its factorization.

12051721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1092 (or 1081 counting only the distinct ones).

The product of its (nonzero) digits is 140, while the sum is 19.

The square root of 12051721 is about 3471.5588717462. The cubic root of 12051721 is about 229.2712979987.

Adding to 12051721 its reverse (12715021), we get a palindrome (24766742).

It can be divided in two parts, 1205 and 1721, that added together give a triangular number (2926 = T₇₆).

The spelling of 12051721 in words is "twelve million, fifty-one thousand, seven hundred twenty-one".