13121666 has 8 divisors (see below), whose sum is σ = 20718480. Its totient is φ = 6215508.

The previous prime is 13121657. The next prime is 13121683. The reversal of 13121666 is 66612131.

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 172616 + ... + 172691.

It is an arithmetic number, because the mean of its divisors is an integer number (2589810).

Almost surely, 2^13121666 is an apocalyptic number.

13121666 is a deficient number, since it is larger than the sum of its proper divisors (7596814).

13121666 is a wasteful number, since it uses less digits than its factorization.

13121666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 345328.

The product of its digits is 1296, while the sum is 26.

The square root of 13121666 is about 3622.3840216079. The cubic root of 13121666 is about 235.8647242555.

Adding to 13121666 its reverse (66612131), we get a palindrome (79733797).

The spelling of 13121666 in words is "thirteen million, one hundred twenty-one thousand, six hundred sixty-six".