666618706 has 32 divisors (see below), whose sum is σ = 1125815040. Its totient is φ = 293730624.

The previous prime is 666618691. The next prime is 666618721. The reversal of 666618706 is 607816666.

It is an interprime number because it is at equal distance from previous prime (666618691) and next prime (666618721).

It is a super-2 number, since 2×666618706² = 888760998378228872, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (46).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 548956 + ... + 550168.

It is an arithmetic number, because the mean of its divisors is an integer number (35181720).

Almost surely, 2^666618706 is an apocalyptic number.

666618706 is a deficient number, since it is larger than the sum of its proper divisors (459196334).

666618706 is a wasteful number, since it uses less digits than its factorization.

666618706 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2170.

The product of its (nonzero) digits is 435456, while the sum is 46.

The square root of 666618706 is about 25818.9602036953. The cubic root of 666618706 is about 873.5595154832.

The spelling of 666618706 in words is "six hundred sixty-six million, six hundred eighteen thousand, seven hundred six".