666383409 has 32 divisors (see below), whose sum is σ = 1072742400. Its totient is φ = 407287440.

The previous prime is 666383383. The next prime is 666383411. The reversal of 666383409 is 904383666.

It is not a de Polignac number, because 666383409 - 2⁷ = 666383281 is a prime.

It is a super-2 number, since 2×666383409² = 888133695580922562, which contains 22 as substring.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (666383449) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 5049 + ... + 36854.

It is an arithmetic number, because the mean of its divisors is an integer number (33523200).

Almost surely, 2^666383409 is an apocalyptic number.

It is an amenable number.

666383409 is a deficient number, since it is larger than the sum of its proper divisors (406358991).

666383409 is a wasteful number, since it uses less digits than its factorization.

666383409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41962 (or 41956 counting only the distinct ones).

The product of its (nonzero) digits is 559872, while the sum is 45.

The square root of 666383409 is about 25814.4031308105. The cubic root of 666383409 is about 873.4567230272.

The spelling of 666383409 in words is "six hundred sixty-six million, three hundred eighty-three thousand, four hundred nine".