12356666678 has 4 divisors (see below), whose sum is σ = 18535000020. Its totient is φ = 6178333338.

The previous prime is 12356666669. The next prime is 12356666747. The reversal of 12356666678 is 87666665321.

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

It is a super-2 number, since 2×12356666678² (a number of 21 digits) contains 22 as substring.

It is a Curzon number.

It is a plaindrome in base 10.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3089166668 + ... + 3089166671.

It is an arithmetic number, because the mean of its divisors is an integer number (4633750005).

Almost surely, 2^12356666678 is an apocalyptic number.

12356666678 is a deficient number, since it is larger than the sum of its proper divisors (6178333342).

12356666678 is an equidigital number, since it uses as much as digits as its factorization.

12356666678 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6178333341.

The product of its digits is 13063680, while the sum is 56.

The spelling of 12356666678 in words is "twelve billion, three hundred fifty-six million, six hundred sixty-six thousand, six hundred seventy-eight".