646536 has 64 divisors (see below), whose sum is σ = 1843200. Its totient is φ = 187200.

The previous prime is 646523. The next prime is 646537. The reversal of 646536 is 635646.

646536 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an Ulam number.

It is a nialpdrome in base 15.

It is not an unprimeable number, because it can be changed into a prime (646537) by changing a digit.

646536 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 8145 + ... + 8223.

It is an arithmetic number, because the mean of its divisors is an integer number (28800).

2⁶⁴⁶⁵³⁶ is an apocalyptic number.

646536 is a gapful number since it is divisible by the number (66) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (921600).

646536 is an abundant number, since it is smaller than the sum of its proper divisors (1196664).

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

646536 is a wasteful number, since it uses less digits than its factorization.

646536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130 (or 126 counting only the distinct ones).

The product of its digits is 12960, while the sum is 30.

The square root of 646536 is about 804.0746234026. The cubic root of 646536 is about 86.4697567655.

The spelling of 646536 in words is "six hundred forty-six thousand, five hundred thirty-six".