646319 has 4 divisors (see below), whose sum is σ = 667200. Its totient is φ = 625440.

The previous prime is 646309. The next prime is 646339. The reversal of 646319 is 913646.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 646319 - 2¹² = 642223 is a prime.

It is a super-2 number, since 2×646319² = 835456499522, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 646291 and 646300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646309) 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 3 ways as a sum of consecutive naturals, for example, 10394 + ... + 10455.

It is an arithmetic number, because the mean of its divisors is an integer number (166800).

2⁶⁴⁶³¹⁹ is an apocalyptic number.

646319 is a deficient number, since it is larger than the sum of its proper divisors (20881).

646319 is a wasteful number, since it uses less digits than its factorization.

646319 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20880.

The product of its digits is 3888, while the sum is 29.

The square root of 646319 is about 803.9396743537. The cubic root of 646319 is about 86.4600815956.

The spelling of 646319 in words is "six hundred forty-six thousand, three hundred nineteen".