666707667 has 4 divisors (see below), whose sum is σ = 888943560. Its totient is φ = 444471776.

The previous prime is 666707641. The next prime is 666707677. The reversal of 666707667 is 766707666.

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 666707667 - 2⁶ = 666707603 is a prime.

It is a super-2 number, since 2×666707667² = 888998226473165778, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (666707677) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 111117942 + ... + 111117947.

It is an arithmetic number, because the mean of its divisors is an integer number (222235890).

Almost surely, 2^666707667 is an apocalyptic number.

666707667 is a deficient number, since it is larger than the sum of its proper divisors (222235893).

666707667 is a wasteful number, since it uses less digits than its factorization.

666707667 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 222235892.

The product of its (nonzero) digits is 2667168, while the sum is 51.

The square root of 666707667 is about 25820.6829305501. The cubic root of 666707667 is about 873.5983729143.

Subtracting 666707667 from its reverse (766707666), we obtain a palindrome (99999999).

The spelling of 666707667 in words is "six hundred sixty-six million, seven hundred seven thousand, six hundred sixty-seven".