12640765 has 8 divisors (see below), whose sum is σ = 15455448. Its totient is φ = 9921600.

The previous prime is 12640763. The next prime is 12640783. The reversal of 12640765 is 56704621.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 1954404 + 10686361 = 1398^2 + 3269^2 .

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

It is not a de Polignac number, because 12640765 - 2¹ = 12640763 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12640763) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 23586 + ... + 24115.

It is an arithmetic number, because the mean of its divisors is an integer number (1931931).

Almost surely, 2^12640765 is an apocalyptic number.

It is an amenable number.

12640765 is a deficient number, since it is larger than the sum of its proper divisors (2814683).

12640765 is an equidigital number, since it uses as much as digits as its factorization.

12640765 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 47759.

The product of its (nonzero) digits is 10080, while the sum is 31.

The square root of 12640765 is about 3555.3853518290. The cubic root of 12640765 is about 232.9473562045.

The spelling of 12640765 in words is "twelve million, six hundred forty thousand, seven hundred sixty-five".