12640071 has 4 divisors (see below), whose sum is σ = 16853432. Its totient is φ = 8426712.

The previous prime is 12640037. The next prime is 12640091. The reversal of 12640071 is 17004621.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 12640071 - 2⁷ = 12639943 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 (12640021) 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 3 ways as a sum of consecutive naturals, for example, 2106676 + ... + 2106681.

It is an arithmetic number, because the mean of its divisors is an integer number (4213358).

Almost surely, 2^12640071 is an apocalyptic number.

12640071 is a deficient number, since it is larger than the sum of its proper divisors (4213361).

12640071 is an equidigital number, since it uses as much as digits as its factorization.

12640071 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4213360.

The product of its (nonzero) digits is 336, while the sum is 21.

The square root of 12640071 is about 3555.2877520673. The cubic root of 12640071 is about 232.9430930547.

Adding to 12640071 its reverse (17004621), we get a palindrome (29644692).

The spelling of 12640071 in words is "twelve million, six hundred forty thousand, seventy-one".