66720103 has 2 divisors, whose sum is σ = 66720104. Its totient is φ = 66720102.

The previous prime is 66720089. The next prime is 66720107. The reversal of 66720103 is 30102766.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 66720103 - 2¹⁷ = 66589031 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66720107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 33360051 + 33360052.

It is an arithmetic number, because the mean of its divisors is an integer number (33360052).

Almost surely, 2^66720103 is an apocalyptic number.

66720103 is a deficient number, since it is larger than the sum of its proper divisors (1).

66720103 is an equidigital number, since it uses as much as digits as its factorization.

66720103 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1512, while the sum is 25.

The square root of 66720103 is about 8168.2374475770. The cubic root of 66720103 is about 405.5884409632.

Adding to 66720103 its reverse (30102766), we get a palindrome (96822869).

The spelling of 66720103 in words is "sixty-six million, seven hundred twenty thousand, one hundred three".