12911765 has 4 divisors (see below), whose sum is σ = 15494124. Its totient is φ = 10329408.

The previous prime is 12911741. The next prime is 12911777. The reversal of 12911765 is 56711921.

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 4490161 + 8421604 = 2119^2 + 2902^2 .

It is a cyclic number.

It is not a de Polignac number, because 12911765 - 2¹⁴ = 12895381 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1291172 + ... + 1291181.

It is an arithmetic number, because the mean of its divisors is an integer number (3873531).

Almost surely, 2^12911765 is an apocalyptic number.

It is an amenable number.

12911765 is a deficient number, since it is larger than the sum of its proper divisors (2582359).

12911765 is an equidigital number, since it uses as much as digits as its factorization.

12911765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2582358.

The product of its digits is 3780, while the sum is 32.

The square root of 12911765 is about 3593.2944493876. The cubic root of 12911765 is about 234.6002862547.

The spelling of 12911765 in words is "twelve million, nine hundred eleven thousand, seven hundred sixty-five".