66661003 has 2 divisors, whose sum is σ = 66661004. Its totient is φ = 66661002.

The previous prime is 66660953. The next prime is 66661009. The reversal of 66661003 is 30016666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66661003 - 2⁹ = 66660491 is a prime.

It is not a weakly prime, because it can be changed into another prime (66661009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33330501 + 33330502.

It is an arithmetic number, because the mean of its divisors is an integer number (33330502).

Almost surely, 2^66661003 is an apocalyptic number.

66661003 is a deficient number, since it is larger than the sum of its proper divisors (1).

66661003 is an equidigital number, since it uses as much as digits as its factorization.

66661003 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3888, while the sum is 28.

The square root of 66661003 is about 8164.6189745756. The cubic root of 66661003 is about 405.4686501915.

Adding to 66661003 its reverse (30016666), we get a palindrome (96677669).

The spelling of 66661003 in words is "sixty-six million, six hundred sixty-one thousand, three".