66646903 has 2 divisors, whose sum is σ = 66646904. Its totient is φ = 66646902.

The previous prime is 66646897. The next prime is 66646907. The reversal of 66646903 is 30964666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66646903 - 2¹³ = 66638711 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66646907) 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, 33323451 + 33323452.

It is an arithmetic number, because the mean of its divisors is an integer number (33323452).

Almost surely, 2^66646903 is an apocalyptic number.

66646903 is a deficient number, since it is larger than the sum of its proper divisors (1).

66646903 is an equidigital number, since it uses as much as digits as its factorization.

66646903 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 139968, while the sum is 40.

The square root of 66646903 is about 8163.7554470966. The cubic root of 66646903 is about 405.4400602071.

The spelling of 66646903 in words is "sixty-six million, six hundred forty-six thousand, nine hundred three".