12729657 has 4 divisors (see below), whose sum is σ = 16972880. Its totient is φ = 8486436.

The previous prime is 12729653. The next prime is 12729671. The reversal of 12729657 is 75692721.

12729657 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 12729657 - 2² = 12729653 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12729653) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2121607 + ... + 2121612.

It is an arithmetic number, because the mean of its divisors is an integer number (4243220).

Almost surely, 2^12729657 is an apocalyptic number.

It is an amenable number.

12729657 is a deficient number, since it is larger than the sum of its proper divisors (4243223).

12729657 is an equidigital number, since it uses as much as digits as its factorization.

12729657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4243222.

The product of its digits is 52920, while the sum is 39.

The square root of 12729657 is about 3567.8644873369. The cubic root of 12729657 is about 233.4921229806.

The spelling of 12729657 in words is "twelve million, seven hundred twenty-nine thousand, six hundred fifty-seven".