646493 has 6 divisors (see below), whose sum is σ = 687066. Its totient is φ = 608192.

The previous prime is 646453. The next prime is 646519. The reversal of 646493 is 394646.

It can be written as a sum of positive squares in 3 ways, for example, as 362404 + 284089 = 602^2 + 533^2 .

It is not a de Polignac number, because 646493 - 2⁸ = 646237 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646403) 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 5 ways as a sum of consecutive naturals, for example, 830 + ... + 1407.

It is an arithmetic number, because the mean of its divisors is an integer number (114511).

2⁶⁴⁶⁴⁹³ is an apocalyptic number.

It is an amenable number.

646493 is a deficient number, since it is larger than the sum of its proper divisors (40573).

646493 is a wasteful number, since it uses less digits than its factorization.

646493 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2271 (or 2254 counting only the distinct ones).

The product of its digits is 15552, while the sum is 32.

The square root of 646493 is about 804.0478841462. The cubic root of 646493 is about 86.4678397379.

The spelling of 646493 in words is "six hundred forty-six thousand, four hundred ninety-three".