666625706 has 4 divisors (see below), whose sum is σ = 999938562. Its totient is φ = 333312852.

The previous prime is 666625703. The next prime is 666625711. The reversal of 666625706 is 607526666.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 607526666 = 2 ⋅303763333.

It can be written as a sum of positive squares in only one way, i.e., 531717481 + 134908225 = 23059^2 + 11615^2 .

It is a super-3 number, since 3×666625706³ (a number of 27 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (666625703) 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, 166656425 + ... + 166656428.

Almost surely, 2^666625706 is an apocalyptic number.

666625706 is a deficient number, since it is larger than the sum of its proper divisors (333312856).

666625706 is a wasteful number, since it uses less digits than its factorization.

666625706 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333312855.

The product of its (nonzero) digits is 544320, while the sum is 44.

The square root of 666625706 is about 25819.0957626327. The cubic root of 666625706 is about 873.5625731508.

The spelling of 666625706 in words is "six hundred sixty-six million, six hundred twenty-five thousand, seven hundred six".