666730423 has 4 divisors (see below), whose sum is σ = 688237888. Its totient is φ = 645222960.

The previous prime is 666730411. The next prime is 666730439. The reversal of 666730423 is 324037666.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 666730423 - 2²¹ = 664633271 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (666730483) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10753686 + ... + 10753747.

It is an arithmetic number, because the mean of its divisors is an integer number (172059472).

Almost surely, 2^666730423 is an apocalyptic number.

666730423 is a deficient number, since it is larger than the sum of its proper divisors (21507465).

666730423 is a wasteful number, since it uses less digits than its factorization.

666730423 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21507464.

The product of its (nonzero) digits is 108864, while the sum is 37.

The square root of 666730423 is about 25821.1235812851. The cubic root of 666730423 is about 873.6083119922.

The spelling of 666730423 in words is "six hundred sixty-six million, seven hundred thirty thousand, four hundred twenty-three".