66550666 has 32 divisors (see below), whose sum is σ = 123516288. Its totient is φ = 26187840.

The previous prime is 66550657. The next prime is 66550681. The reversal of 66550666 is 66605566.

It is a happy number.

It is a super-2 number, since 2×66550666² = 8857982290087112, which contains 22 as substring.

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, 37536 + ... + 39268.

It is an arithmetic number, because the mean of its divisors is an integer number (3859884).

Almost surely, 2^66550666 is an apocalyptic number.

66550666 is a deficient number, since it is larger than the sum of its proper divisors (56965622).

66550666 is a wasteful number, since it uses less digits than its factorization.

66550666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1966.

The product of its (nonzero) digits is 194400, while the sum is 40.

The square root of 66550666 is about 8157.8591554402. The cubic root of 66550666 is about 405.2448166724.

The spelling of 66550666 in words is "sixty-six million, five hundred fifty thousand, six hundred sixty-six".