12640265 has 24 divisors (see below), whose sum is σ = 17667720. Its totient is φ = 8645120.

The previous prime is 12640261. The next prime is 12640283. The reversal of 12640265 is 56204621.

It can be written as a sum of positive squares in 4 ways, for example, as 6568969 + 6071296 = 2563^2 + 2464^2 .

It is not a de Polignac number, because 12640265 - 2² = 12640261 is a prime.

It is not an unprimeable number, because it can be changed into a prime (12640261) 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 23 ways as a sum of consecutive naturals, for example, 9671 + ... + 10899.

It is an arithmetic number, because the mean of its divisors is an integer number (736155).

Almost surely, 2^12640265 is an apocalyptic number.

It is an amenable number.

12640265 is a deficient number, since it is larger than the sum of its proper divisors (5027455).

12640265 is a wasteful number, since it uses less digits than its factorization.

12640265 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1273 (or 1262 counting only the distinct ones).

The product of its (nonzero) digits is 2880, while the sum is 26.

The square root of 12640265 is about 3555.3150352676. The cubic root of 12640265 is about 232.9442847867.

Adding to 12640265 its reverse (56204621), we get a palindrome (68844886).

The spelling of 12640265 in words is "twelve million, six hundred forty thousand, two hundred sixty-five".