646812 has 48 divisors (see below), whose sum is σ = 1723680. Its totient is φ = 209664.

The previous prime is 646781. The next prime is 646823. The reversal of 646812 is 218646.

646812 is a `hidden beast` number, since 646 + 8 + 12 = 666.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 646812.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5668 + ... + 5780.

It is an arithmetic number, because the mean of its divisors is an integer number (35910).

2⁶⁴⁶⁸¹² is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646812, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (861840).

646812 is an abundant number, since it is smaller than the sum of its proper divisors (1076868).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

646812 is a wasteful number, since it uses less digits than its factorization.

646812 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 179 (or 171 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 646812 is about 804.2462309517. The cubic root of 646812 is about 86.4820593842.

The spelling of 646812 in words is "six hundred forty-six thousand, eight hundred twelve".