665031 has 4 divisors (see below), whose sum is σ = 886712. Its totient is φ = 443352.

The previous prime is 665029. The next prime is 665039. The reversal of 665031 is 130566.

665031 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 665031 - 2¹ = 665029 is a prime.

It is a super-2 number, since 2×665031² = 884532461922, which contains 22 as substring.

It is an Ulam number.

It is a D-number.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 664989 and 665007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (665039) 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, 110836 + ... + 110841.

It is an arithmetic number, because the mean of its divisors is an integer number (221678).

2⁶⁶⁵⁰³¹ is an apocalyptic number.

665031 is a deficient number, since it is larger than the sum of its proper divisors (221681).

665031 is a wasteful number, since it uses less digits than its factorization.

665031 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 221680.

The product of its (nonzero) digits is 540, while the sum is 21.

The square root of 665031 is about 815.4943286130. The cubic root of 665031 is about 87.2865436420.

Adding to 665031 its reverse (130566), we get a palindrome (795597).

The spelling of 665031 in words is "six hundred sixty-five thousand, thirty-one".