646711 has 4 divisors (see below), whose sum is σ = 696472. Its totient is φ = 596952.

The previous prime is 646687. The next prime is 646721. The reversal of 646711 is 117646.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 646711 - 2⁹ = 646199 is a prime.

It is a Duffinian number.

646711 is a lucky number.

It is a nialpdrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646721) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 24861 + ... + 24886.

It is an arithmetic number, because the mean of its divisors is an integer number (174118).

2⁶⁴⁶⁷¹¹ is an apocalyptic number.

646711 is a deficient number, since it is larger than the sum of its proper divisors (49761).

646711 is a wasteful number, since it uses less digits than its factorization.

646711 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 49760.

The product of its digits is 1008, while the sum is 25.

The square root of 646711 is about 804.1834367854. The cubic root of 646711 is about 86.4775577450.

The spelling of 646711 in words is "six hundred forty-six thousand, seven hundred eleven".