665311 has 2 divisors, whose sum is σ = 665312. Its totient is φ = 665310.

The previous prime is 665303. The next prime is 665351. The reversal of 665311 is 113566.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 665311 - 2³ = 665303 is a prime.

It is a nialpdrome in base 10.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (665351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332655 + 332656.

It is an arithmetic number, because the mean of its divisors is an integer number (332656).

2⁶⁶⁵³¹¹ is an apocalyptic number.

665311 is a deficient number, since it is larger than the sum of its proper divisors (1).

665311 is an equidigital number, since it uses as much as digits as its factorization.

665311 is an evil number, because the sum of its binary digits is even.

The product of its digits is 540, while the sum is 22.

The square root of 665311 is about 815.6659855603. The cubic root of 665311 is about 87.2987920950.

Adding to 665311 its reverse (113566), we get a palindrome (778877).

The spelling of 665311 in words is "six hundred sixty-five thousand, three hundred eleven".