12140721 has 12 divisors (see below), whose sum is σ = 17566848. Its totient is φ = 8079864.

The previous prime is 12140693. The next prime is 12140731. The reversal of 12140721 is 12704121.

It is not a de Polignac number, because 12140721 - 2⁷ = 12140593 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 12140694 and 12140703.

It is not an unprimeable number, because it can be changed into a prime (12140731) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9316 + ... + 10538.

It is an arithmetic number, because the mean of its divisors is an integer number (1463904).

Almost surely, 2^12140721 is an apocalyptic number.

It is an amenable number.

12140721 is a deficient number, since it is larger than the sum of its proper divisors (5426127).

12140721 is a wasteful number, since it uses less digits than its factorization.

12140721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2332 (or 2329 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 12140721 is about 3484.3537420876. The cubic root of 12140721 is about 229.8342914784.

Adding to 12140721 its reverse (12704121), we get a palindrome (24844842).

The spelling of 12140721 in words is "twelve million, one hundred forty thousand, seven hundred twenty-one".