12666501 has 6 divisors (see below), whose sum is σ = 18296070. Its totient is φ = 8444328.

The previous prime is 12666461. The next prime is 12666503. The reversal of 12666501 is 10566621.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 8468100 + 4198401 = 2910^2 + 2049^2 .

It is not a de Polignac number, because 12666501 - 2¹³ = 12658309 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (12666503) 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, 703686 + ... + 703703.

It is an arithmetic number, because the mean of its divisors is an integer number (3049345).

Almost surely, 2^12666501 is an apocalyptic number.

It is an amenable number.

12666501 is a deficient number, since it is larger than the sum of its proper divisors (5629569).

12666501 is a wasteful number, since it uses less digits than its factorization.

12666501 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1407395 (or 1407392 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 27.

The square root of 12666501 is about 3559.0028097769. The cubic root of 12666501 is about 233.1053389730.

The spelling of 12666501 in words is "twelve million, six hundred sixty-six thousand, five hundred one".