66388853 has 2 divisors, whose sum is σ = 66388854. Its totient is φ = 66388852.

The previous prime is 66388849. The next prime is 66388873. The reversal of 66388853 is 35888366.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 66210769 + 178084 = 8137^2 + 422^2 .

It is a cyclic number.

It is not a de Polignac number, because 66388853 - 2² = 66388849 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 66388798 and 66388807.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66388873) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33194426 + 33194427.

It is an arithmetic number, because the mean of its divisors is an integer number (33194427).

Almost surely, 2^66388853 is an apocalyptic number.

It is an amenable number.

66388853 is a deficient number, since it is larger than the sum of its proper divisors (1).

66388853 is an equidigital number, since it uses as much as digits as its factorization.

66388853 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 829440, while the sum is 47.

The square root of 66388853 is about 8147.9355053903. The cubic root of 66388853 is about 404.9161092310.

The spelling of 66388853 in words is "sixty-six million, three hundred eighty-eight thousand, eight hundred fifty-three".