643056 has 20 divisors (see below), whose sum is σ = 1661352. Its totient is φ = 214336.

The previous prime is 643051. The next prime is 643061. The reversal of 643056 is 650346.

It is an interprime number because it is at equal distance from previous prime (643051) and next prime (643061).

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (643051) by changing a digit.

643056 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 3 ways as a sum of consecutive naturals, for example, 6651 + ... + 6746.

2⁶⁴³⁰⁵⁶ is an apocalyptic number.

It is an amenable number.

643056 is an abundant number, since it is smaller than the sum of its proper divisors (1018296).

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

643056 is a wasteful number, since it uses less digits than its factorization.

643056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13408 (or 13402 counting only the distinct ones).

The product of its (nonzero) digits is 2160, while the sum is 24.

The square root of 643056 is about 801.9077253650. The cubic root of 643056 is about 86.3143355318.

The spelling of 643056 in words is "six hundred forty-three thousand, fifty-six".