12644657 has 4 divisors (see below), whose sum is σ = 12694116. Its totient is φ = 12595200.

The previous prime is 12644591. The next prime is 12644669. The reversal of 12644657 is 75644621.

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 7187761 + 5456896 = 2681^2 + 2336^2 .

It is a cyclic number.

It is not a de Polignac number, because 12644657 - 2¹² = 12640561 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (12644057) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24344 + ... + 24857.

It is an arithmetic number, because the mean of its divisors is an integer number (3173529).

Almost surely, 2^12644657 is an apocalyptic number.

It is an amenable number.

12644657 is a deficient number, since it is larger than the sum of its proper divisors (49459).

12644657 is an equidigital number, since it uses as much as digits as its factorization.

12644657 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 49458.

The product of its digits is 40320, while the sum is 35.

The square root of 12644657 is about 3555.9326484060. The cubic root of 12644657 is about 232.9712613526.

The spelling of 12644657 in words is "twelve million, six hundred forty-four thousand, six hundred fifty-seven".