665043943 has 16 divisors (see below), whose sum is σ = 688377600. Its totient is φ = 642223296.

The previous prime is 665043941. The next prime is 665043991. The reversal of 665043943 is 349340566.

It is a cyclic number.

It is not a de Polignac number, because 665043943 - 2¹ = 665043941 is a prime.

It is a super-2 number, since 2×665043943² = 884566892241974498, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 665043896 and 665043905.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665043941) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1109958 + ... + 1110556.

It is an arithmetic number, because the mean of its divisors is an integer number (43023600).

Almost surely, 2^665043943 is an apocalyptic number.

665043943 is a deficient number, since it is larger than the sum of its proper divisors (23333657).

665043943 is a wasteful number, since it uses less digits than its factorization.

665043943 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 966.

The product of its (nonzero) digits is 233280, while the sum is 40.

The square root of 665043943 is about 25788.4459206056. The cubic root of 665043943 is about 872.8710990249.

The spelling of 665043943 in words is "six hundred sixty-five million, forty-three thousand, nine hundred forty-three".