66404197668 has 48 divisors (see below), whose sum is σ = 163487520000. Its totient is φ = 20919669408.

The previous prime is 66404197637. The next prime is 66404197711. The reversal of 66404197668 is 86679140466.

It is a Harshad number since it is a multiple of its sum of digits (57).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 252018 + ... + 443081.

It is an arithmetic number, because the mean of its divisors is an integer number (3405990000).

Almost surely, 2^66404197668 is an apocalyptic number.

It is an amenable number.

66404197668 is an abundant number, since it is smaller than the sum of its proper divisors (97083322332).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

66404197668 is a wasteful number, since it uses less digits than its factorization.

66404197668 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 695544 (or 695542 counting only the distinct ones).

The product of its (nonzero) digits is 10450944, while the sum is 57.

The spelling of 66404197668 in words is "sixty-six billion, four hundred four million, one hundred ninety-seven thousand, six hundred sixty-eight".