12640025 has 6 divisors (see below), whose sum is σ = 15673662. Its totient is φ = 10112000.

The previous prime is 12640021. The next prime is 12640037. The reversal of 12640025 is 52004621.

It is a happy number.

12640025 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 3 ways, for example, as 80089 + 12559936 = 283^2 + 3544^2 .

It is not a de Polignac number, because 12640025 - 2² = 12640021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 12639979 and 12640006.

It is not an unprimeable number, because it can be changed into a prime (12640021) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 252776 + ... + 252825.

It is an arithmetic number, because the mean of its divisors is an integer number (2612277).

Almost surely, 2^12640025 is an apocalyptic number.

It is an amenable number.

12640025 is a deficient number, since it is larger than the sum of its proper divisors (3033637).

12640025 is an equidigital number, since it uses as much as digits as its factorization.

12640025 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 505611 (or 505606 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 12640025 is about 3555.2812828242. The cubic root of 12640025 is about 232.9428104773.

Adding to 12640025 its reverse (52004621), we get a palindrome (64644646).

The spelling of 12640025 in words is "twelve million, six hundred forty thousand, twenty-five".