18440666 has 8 divisors (see below), whose sum is σ = 28114644. Its totient is φ = 9069120.

The previous prime is 18440663. The next prime is 18440671. The reversal of 18440666 is 66604481.

It can be written as a sum of positive squares in 2 ways, for example, as 17682025 + 758641 = 4205^2 + 871^2 .

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

It is not an unprimeable number, because it can be changed into a prime (18440663) 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, 75455 + ... + 75698.

Almost surely, 2^18440666 is an apocalyptic number.

18440666 is a deficient number, since it is larger than the sum of its proper divisors (9673978).

18440666 is a wasteful number, since it uses less digits than its factorization.

18440666 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 151216.

The product of its (nonzero) digits is 27648, while the sum is 35.

The square root of 18440666 is about 4294.2596567977. The cubic root of 18440666 is about 264.1955717204.

The spelling of 18440666 in words is "eighteen million, four hundred forty thousand, six hundred sixty-six".