646726 has 8 divisors (see below), whose sum is σ = 975744. Its totient is φ = 321480.

The previous prime is 646721. The next prime is 646757. The reversal of 646726 is 627646.

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

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 (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 465 + ... + 1228.

It is an arithmetic number, because the mean of its divisors is an integer number (121968).

2⁶⁴⁶⁷²⁶ is an apocalyptic number.

646726 is a deficient number, since it is larger than the sum of its proper divisors (329018).

646726 is a wasteful number, since it uses less digits than its factorization.

646726 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1886.

The product of its digits is 12096, while the sum is 31.

The square root of 646726 is about 804.1927629617. The cubic root of 646726 is about 86.4782263349.

It can be divided in two parts, 646 and 726, that multiplied together give a triangular number (468996 = T₉₆₈).

The spelling of 646726 in words is "six hundred forty-six thousand, seven hundred twenty-six".