12145729 has 4 divisors (see below), whose sum is σ = 12187476. Its totient is φ = 12103984.

The previous prime is 12145723. The next prime is 12145733. The reversal of 12145729 is 92754121.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6385729 + 5760000 = 2527^2 + 2400^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12145729 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a nialpdrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 12145729.

It is not an unprimeable number, because it can be changed into a prime (12145723) 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, 20434 + ... + 21019.

It is an arithmetic number, because the mean of its divisors is an integer number (3046869).

Almost surely, 2^12145729 is an apocalyptic number.

It is an amenable number.

12145729 is a deficient number, since it is larger than the sum of its proper divisors (41747).

12145729 is an equidigital number, since it uses as much as digits as its factorization.

12145729 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41746.

The product of its digits is 5040, while the sum is 31.

The square root of 12145729 is about 3485.0723091494. The cubic root of 12145729 is about 229.8658890501.

It can be divided in two parts, 121457 and 29, that multiplied together give a palindrome (3522253).

The spelling of 12145729 in words is "twelve million, one hundred forty-five thousand, seven hundred twenty-nine".