66398808447 has 12 divisors (see below), whose sum is σ = 97534973640. Its totient is φ = 43515602928.

The previous prime is 66398808419. The next prime is 66398808473. The reversal of 66398808447 is 74480889366.

It is not a de Polignac number, because 66398808447 - 2¹⁹ = 66398284159 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66398803447) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 62521888 + ... + 62522949.

It is an arithmetic number, because the mean of its divisors is an integer number (8127914470).

Almost surely, 2^66398808447 is an apocalyptic number.

66398808447 is a deficient number, since it is larger than the sum of its proper divisors (31136165193).

66398808447 is a wasteful number, since it uses less digits than its factorization.

66398808447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 125044902 (or 125044899 counting only the distinct ones).

The product of its (nonzero) digits is 55738368, while the sum is 63.

The spelling of 66398808447 in words is "sixty-six billion, three hundred ninety-eight million, eight hundred eight thousand, four hundred forty-seven".