666220443 has 8 divisors (see below), whose sum is σ = 1015193088. Its totient is φ = 380697384.

The previous prime is 666220433. The next prime is 666220453. The reversal of 666220443 is 344022666.

It is an interprime number because it is at equal distance from previous prime (666220433) and next prime (666220453).

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

It is a de Polignac number, because none of the positive numbers 2^k-666220443 is a prime.

It is a super-2 number, since 2×666220443² = 887699357342232498, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (666220433) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15862371 + ... + 15862412.

It is an arithmetic number, because the mean of its divisors is an integer number (126899136).

Almost surely, 2^666220443 is an apocalyptic number.

666220443 is a deficient number, since it is larger than the sum of its proper divisors (348972645).

666220443 is a wasteful number, since it uses less digits than its factorization.

666220443 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31724793.

The product of its (nonzero) digits is 41472, while the sum is 33.

The square root of 666220443 is about 25811.2464441375. The cubic root of 666220443 is about 873.3855150952.

The spelling of 666220443 in words is "six hundred sixty-six million, two hundred twenty thousand, four hundred forty-three".