1213660666 has 8 divisors (see below), whose sum is σ = 1820710944. Its totient is φ = 606757020.

The previous prime is 1213660601. The next prime is 1213660729. The reversal of 1213660666 is 6660663121.

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12880 + ... + 50923.

It is an arithmetic number, because the mean of its divisors is an integer number (227588868).

Almost surely, 2^1213660666 is an apocalyptic number.

1213660666 is a deficient number, since it is larger than the sum of its proper divisors (607050278).

1213660666 is an equidigital number, since it uses as much as digits as its factorization.

1213660666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 73316.

The product of its (nonzero) digits is 46656, while the sum is 37.

The square root of 1213660666 is about 34837.6328989212. The cubic root of 1213660666 is about 1066.6757592758.

The spelling of 1213660666 in words is "one billion, two hundred thirteen million, six hundred sixty thousand, six hundred sixty-six".