6663665605121 has 16 divisors (see below), whose sum is σ = 8414186459904. Its totient is φ = 5142002832384.

The previous prime is 6663665605097. The next prime is 6663665605127. The reversal of 6663665605121 is 1215065663666.

It is a cyclic number.

It is not a de Polignac number, because 6663665605121 - 2⁶ = 6663665605057 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6663665605127) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 1217327480 + ... + 1217332953.

It is an arithmetic number, because the mean of its divisors is an integer number (525886653744).

Almost surely, 2^{6663665605121} is an apocalyptic number.

It is an amenable number.

6663665605121 is a deficient number, since it is larger than the sum of its proper divisors (1750520854783).

6663665605121 is a wasteful number, since it uses less digits than its factorization.

6663665605121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2434660480.

The product of its (nonzero) digits is 6998400, while the sum is 53.

The spelling of 6663665605121 in words is "six trillion, six hundred sixty-three billion, six hundred sixty-five million, six hundred five thousand, one hundred twenty-one".