66573641 has 2 divisors, whose sum is σ = 66573642. Its totient is φ = 66573640.

The previous prime is 66573629. The next prime is 66573673. The reversal of 66573641 is 14637566.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 36048016 + 30525625 = 6004^2 + 5525^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66573641 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 = 66573595 and 66573604.

It is not a weakly prime, because it can be changed into another prime (66573541) 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 as a sum of consecutive naturals, namely, 33286820 + 33286821.

It is an arithmetic number, because the mean of its divisors is an integer number (33286821).

Almost surely, 2^66573641 is an apocalyptic number.

It is an amenable number.

66573641 is a deficient number, since it is larger than the sum of its proper divisors (1).

66573641 is an equidigital number, since it uses as much as digits as its factorization.

66573641 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 90720, while the sum is 38.

The square root of 66573641 is about 8159.2671852318. The cubic root of 66573641 is about 405.2914449483.

The spelling of 66573641 in words is "sixty-six million, five hundred seventy-three thousand, six hundred forty-one".