646456 has 16 divisors (see below), whose sum is σ = 1276200. Its totient is φ = 306144.

The previous prime is 646453. The next prime is 646519. The reversal of 646456 is 654646.

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 (646453) 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, 1975 + ... + 2278.

2⁶⁴⁶⁴⁵⁶ is an apocalyptic number.

It is an amenable number.

646456 is a deficient number, since it is larger than the sum of its proper divisors (629744).

646456 is a wasteful number, since it uses less digits than its factorization.

646456 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4278 (or 4274 counting only the distinct ones).

The product of its digits is 17280, while the sum is 31.

The square root of 646456 is about 804.0248752371. The cubic root of 646456 is about 86.4661901345.

The spelling of 646456 in words is "six hundred forty-six thousand, four hundred fifty-six".