66961903 has 2 divisors, whose sum is σ = 66961904. Its totient is φ = 66961902.

The previous prime is 66961883. The next prime is 66961907. The reversal of 66961903 is 30916966.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-66961903 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (66961907) 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, 33480951 + 33480952.

It is an arithmetic number, because the mean of its divisors is an integer number (33480952).

Almost surely, 2^66961903 is an apocalyptic number.

66961903 is a deficient number, since it is larger than the sum of its proper divisors (1).

66961903 is an equidigital number, since it uses as much as digits as its factorization.

66961903 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 52488, while the sum is 40.

The square root of 66961903 is about 8183.0252963070. The cubic root of 66961903 is about 406.0778139576.

The spelling of 66961903 in words is "sixty-six million, nine hundred sixty-one thousand, nine hundred three".