6663656405 has 16 divisors (see below), whose sum is σ = 9361626624. Its totient is φ = 4457915520.

The previous prime is 6663656359. The next prime is 6663656407. The reversal of 6663656405 is 5046563666.

It is not a de Polignac number, because 6663656405 - 2¹⁸ = 6663394261 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 6663656405.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6663656407) 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, 2320397 + ... + 2323266.

It is an arithmetic number, because the mean of its divisors is an integer number (585101664).

Almost surely, 2^6663656405 is an apocalyptic number.

It is an amenable number.

6663656405 is a deficient number, since it is larger than the sum of its proper divisors (2697970219).

6663656405 is a wasteful number, since it uses less digits than its factorization.

6663656405 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4643716.

The product of its (nonzero) digits is 2332800, while the sum is 47.

The square root of 6663656405 is about 81631.2219986936. The cubic root of 6663656405 is about 1881.7887386461.

The spelling of 6663656405 in words is "six billion, six hundred sixty-three million, six hundred fifty-six thousand, four hundred five".