646706 has 8 divisors (see below), whose sum is σ = 988524. Its totient is φ = 317200.

The previous prime is 646687. The next prime is 646721. The reversal of 646706 is 607646.

It can be written as a sum of positive squares in 2 ways, for example, as 625681 + 21025 = 791^2 + 145^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is an unprimeable number.

646706 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2945 + ... + 3156.

2⁶⁴⁶⁷⁰⁶ is an apocalyptic number.

646706 is a deficient number, since it is larger than the sum of its proper divisors (341818).

646706 is a wasteful number, since it uses less digits than its factorization.

646706 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6156.

The product of its (nonzero) digits is 6048, while the sum is 29.

The square root of 646706 is about 804.1803280359. The cubic root of 646706 is about 86.4773348794.

Subtracting from 646706 its reverse (607646), we obtain a triangular number (39060 = T₂₇₉).

The spelling of 646706 in words is "six hundred forty-six thousand, seven hundred six".