666718797 has 8 divisors (see below), whose sum is σ = 935745760. Its totient is φ = 421085520.

The previous prime is 666718783. The next prime is 666718823. The reversal of 666718797 is 797817666.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 666718797 - 2¹⁵ = 666686029 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (57), and also a Moran number because the ratio is a prime number: 11696821 = 666718797 / (6 + 6 + 6 + 7 + 1 + 8 + 7 + 9 + 7).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666718757) 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 7 ways as a sum of consecutive naturals, for example, 5848354 + ... + 5848467.

It is an arithmetic number, because the mean of its divisors is an integer number (116968220).

Almost surely, 2^666718797 is an apocalyptic number.

It is an amenable number.

666718797 is a deficient number, since it is larger than the sum of its proper divisors (269026963).

666718797 is a wasteful number, since it uses less digits than its factorization.

666718797 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11696843.

The product of its digits is 5334336, while the sum is 57.

The square root of 666718797 is about 25820.8984545465. The cubic root of 666718797 is about 873.6032341632.

The spelling of 666718797 in words is "six hundred sixty-six million, seven hundred eighteen thousand, seven hundred ninety-seven".