66623873 has 2 divisors, whose sum is σ = 66623874. Its totient is φ = 66623872.

The previous prime is 66623839. The next prime is 66623881. The reversal of 66623873 is 37832666.

66623873 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 35129329 + 31494544 = 5927^2 + 5612^2 .

It is a cyclic number.

It is not a de Polignac number, because 66623873 - 2¹⁰ = 66622849 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 66623873.

It is not a weakly prime, because it can be changed into another prime (66626873) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33311936 + 33311937.

It is an arithmetic number, because the mean of its divisors is an integer number (33311937).

Almost surely, 2^66623873 is an apocalyptic number.

It is an amenable number.

66623873 is a deficient number, since it is larger than the sum of its proper divisors (1).

66623873 is an equidigital number, since it uses as much as digits as its factorization.

66623873 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 217728, while the sum is 41.

The square root of 66623873 is about 8162.3448224147. The cubic root of 66623873 is about 405.3933545595.

The spelling of 66623873 in words is "sixty-six million, six hundred twenty-three thousand, eight hundred seventy-three".