12121666 has 8 divisors (see below), whose sum is σ = 18197820. Its totient is φ = 6055728.

The previous prime is 12121661. The next prime is 12121673. The reversal of 12121666 is 66612121.

12121666 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 2 ways, for example, as 12103441 + 18225 = 3479^2 + 135^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 12121666.

It is not an unprimeable number, because it can be changed into a prime (12121661) 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, 2140 + ... + 5368.

Almost surely, 2^12121666 is an apocalyptic number.

12121666 is a deficient number, since it is larger than the sum of its proper divisors (6076154).

12121666 is a wasteful number, since it uses less digits than its factorization.

12121666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5108.

The product of its digits is 864, while the sum is 25.

The square root of 12121666 is about 3481.6183018820. The cubic root of 12121666 is about 229.7139860027.

Adding to 12121666 its reverse (66612121), we get a palindrome (78733787).

The spelling of 12121666 in words is "twelve million, one hundred twenty-one thousand, six hundred sixty-six".