666662005 has 8 divisors (see below), whose sum is σ = 827580600. Its totient is φ = 514938816.

The previous prime is 666661991. The next prime is 666662011. The reversal of 666662005 is 500266666.

It can be written as a sum of positive squares in 4 ways, for example, as 62583921 + 604078084 = 7911^2 + 24578^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 666662005 - 2¹⁵ = 666629237 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2298690 + ... + 2298979.

It is an arithmetic number, because the mean of its divisors is an integer number (103447575).

Almost surely, 2^666662005 is an apocalyptic number.

It is an amenable number.

666662005 is a deficient number, since it is larger than the sum of its proper divisors (160918595).

666662005 is a wasteful number, since it uses less digits than its factorization.

666662005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4597703.

The product of its (nonzero) digits is 77760, while the sum is 37.

The square root of 666662005 is about 25819.7987017715. The cubic root of 666662005 is about 873.5784285611.

The spelling of 666662005 in words is "six hundred sixty-six million, six hundred sixty-two thousand, five".