646736 has 20 divisors (see below), whose sum is σ = 1270752. Its totient is φ = 318816.

The previous prime is 646721. The next prime is 646757. The reversal of 646736 is 637646.

646736 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

646736 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1085 + ... + 1571.

2⁶⁴⁶⁷³⁶ is an apocalyptic number.

It is an amenable number.

646736 is a deficient number, since it is larger than the sum of its proper divisors (624016).

646736 is a wasteful number, since it uses less digits than its factorization.

646736 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 578 (or 572 counting only the distinct ones).

The product of its digits is 18144, while the sum is 32.

The square root of 646736 is about 804.1989803525. The cubic root of 646736 is about 86.4786720558.

The spelling of 646736 in words is "six hundred forty-six thousand, seven hundred thirty-six".