66386997 has 24 divisors (see below), whose sum is σ = 97593600. Its totient is φ = 43480800.

The previous prime is 66386981. The next prime is 66387031. The reversal of 66386997 is 79968366.

It is a happy number.

It is not a de Polignac number, because 66386997 - 2⁴ = 66386981 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (66386927) 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 23 ways as a sum of consecutive naturals, for example, 180708 + ... + 181074.

It is an arithmetic number, because the mean of its divisors is an integer number (4066400).

Almost surely, 2^66386997 is an apocalyptic number.

It is an amenable number.

66386997 is a deficient number, since it is larger than the sum of its proper divisors (31206603).

66386997 is a wasteful number, since it uses less digits than its factorization.

66386997 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 673 (or 670 counting only the distinct ones).

The product of its digits is 2939328, while the sum is 54.

The square root of 66386997 is about 8147.8216107129. The cubic root of 66386997 is about 404.9123358500.

The spelling of 66386997 in words is "sixty-six million, three hundred eighty-six thousand, nine hundred ninety-seven".