12731905 has 8 divisors (see below), whose sum is σ = 15537600. Its totient is φ = 10012656.

The previous prime is 12731893. The next prime is 12731909. The reversal of 12731905 is 50913721.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 12731905 - 2¹⁹ = 12207617 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12731909) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21285 + ... + 21874.

It is an arithmetic number, because the mean of its divisors is an integer number (1942200).

Almost surely, 2^12731905 is an apocalyptic number.

It is an amenable number.

12731905 is a deficient number, since it is larger than the sum of its proper divisors (2805695).

12731905 is an equidigital number, since it uses as much as digits as its factorization.

12731905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43223.

The product of its (nonzero) digits is 1890, while the sum is 28.

The square root of 12731905 is about 3568.1795078163. The cubic root of 12731905 is about 233.5058667235.

The spelling of 12731905 in words is "twelve million, seven hundred thirty-one thousand, nine hundred five".