646236 has 36 divisors (see below), whose sum is σ = 1692600. Its totient is φ = 207648.

The previous prime is 646199. The next prime is 646237. The reversal of 646236 is 632646.

It is a tau number, because it is divible by the number of its divisors (36).

It is a nude number because it is divisible by every one of its digits.

It is an Ulam number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646237) by changing a digit.

646236 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

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 11 ways as a sum of consecutive naturals, for example, 735 + ... + 1353.

2⁶⁴⁶²³⁶ 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 646236, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (846300).

646236 is an abundant number, since it is smaller than the sum of its proper divisors (1046364).

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

646236 is a wasteful number, since it uses less digits than its factorization.

646236 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 658 (or 653 counting only the distinct ones).

The product of its digits is 5184, while the sum is 27.

The square root of 646236 is about 803.8880519077. Note that the first 3 decimals coincide. The cubic root of 646236 is about 86.4563803820.

The spelling of 646236 in words is "six hundred forty-six thousand, two hundred thirty-six".