66664666 has 8 divisors (see below), whose sum is σ = 100294740. Its totient is φ = 33233088.

The previous prime is 66664627. The next prime is 66664691. The reversal of 66664666 is 66646666.

It can be written as a sum of positive squares in 2 ways, for example, as 65950641 + 714025 = 8121^2 + 845^2 .

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

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 48781 + ... + 50128.

Almost surely, 2^66664666 is an apocalyptic number.

66664666 is a deficient number, since it is larger than the sum of its proper divisors (33630074).

66664666 is a wasteful number, since it uses less digits than its factorization.

66664666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99248.

The product of its digits is 1119744, while the sum is 46.

The square root of 66664666 is about 8164.8432930461. The cubic root of 66664666 is about 405.4760768447.

The spelling of 66664666 in words is "sixty-six million, six hundred sixty-four thousand, six hundred sixty-six".