666729073 has 4 divisors (see below), whose sum is σ = 666790128. Its totient is φ = 666668020.

The previous prime is 666729071. The next prime is 666729101. The reversal of 666729073 is 370927666.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 666729073 - 2¹ = 666729071 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (666729071) 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 in 3 ways as a sum of consecutive naturals, for example, 9163 + ... + 37648.

It is an arithmetic number, because the mean of its divisors is an integer number (166697532).

Almost surely, 2^666729073 is an apocalyptic number.

It is an amenable number.

666729073 is a deficient number, since it is larger than the sum of its proper divisors (61055).

666729073 is a wasteful number, since it uses less digits than its factorization.

666729073 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 61054.

The product of its (nonzero) digits is 571536, while the sum is 46.

The square root of 666729073 is about 25821.0974398843. The cubic root of 666729073 is about 873.6077223626.

The spelling of 666729073 in words is "six hundred sixty-six million, seven hundred twenty-nine thousand, seventy-three".