66040669 has 2 divisors, whose sum is σ = 66040670. Its totient is φ = 66040668.

The previous prime is 66040657. The next prime is 66040717. The reversal of 66040669 is 96604066.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 48818169 + 17222500 = 6987^2 + 4150^2 .

It is a cyclic number.

It is not a de Polignac number, because 66040669 - 2¹⁵ = 66007901 is a prime.

It is a super-2 number, since 2×66040669² = 8722739923935122, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66040619) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33020334 + 33020335.

It is an arithmetic number, because the mean of its divisors is an integer number (33020335).

Almost surely, 2^66040669 is an apocalyptic number.

It is an amenable number.

66040669 is a deficient number, since it is larger than the sum of its proper divisors (1).

66040669 is an equidigital number, since it uses as much as digits as its factorization.

66040669 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 46656, while the sum is 37.

The square root of 66040669 is about 8126.5410230922. The cubic root of 66040669 is about 404.2069916804.

The spelling of 66040669 in words is "sixty-six million, forty thousand, six hundred sixty-nine".