666743923 has 2 divisors, whose sum is σ = 666743924. Its totient is φ = 666743922.

The previous prime is 666743911. The next prime is 666743933. The reversal of 666743923 is 329347666.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 666743923 - 2²⁹ = 129873011 is a prime.

It is not a weakly prime, because it can be changed into another prime (666743933) 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, 333371961 + 333371962.

It is an arithmetic number, because the mean of its divisors is an integer number (333371962).

Almost surely, 2^666743923 is an apocalyptic number.

666743923 is a deficient number, since it is larger than the sum of its proper divisors (1).

666743923 is an equidigital number, since it uses as much as digits as its factorization.

666743923 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 979776, while the sum is 46.

The square root of 666743923 is about 25821.3849938380. The cubic root of 666743923 is about 873.6142082447.

The spelling of 666743923 in words is "six hundred sixty-six million, seven hundred forty-three thousand, nine hundred twenty-three".