66660668121 has 16 divisors (see below), whose sum is σ = 89688487680. Its totient is φ = 44036832000.

The previous prime is 66660668099. The next prime is 66660668131. The reversal of 66660668121 is 12186606666.

It is not a de Polignac number, because 66660668121 - 2¹⁴ = 66660651737 is a prime.

It is not an unprimeable number, because it can be changed into a prime (66660668131) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1589895 + ... + 1631283.

It is an arithmetic number, because the mean of its divisors is an integer number (5605530480).

Almost surely, 2^66660668121 is an apocalyptic number.

It is an amenable number.

66660668121 is a deficient number, since it is larger than the sum of its proper divisors (23027819559).

66660668121 is a wasteful number, since it uses less digits than its factorization.

66660668121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 46256.

The product of its (nonzero) digits is 746496, while the sum is 48.

The spelling of 66660668121 in words is "sixty-six billion, six hundred sixty million, six hundred sixty-eight thousand, one hundred twenty-one".