63644256 has 144 divisors (see below), whose sum is σ = 198132480. Its totient is φ = 19261440.

The previous prime is 63644239. The next prime is 63644263. The reversal of 63644256 is 65244636.

63644256 is a `hidden beast` number, since 6 + 3 + 644 + 2 + 5 + 6 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 63644256.

It is a congruent number.

It is an unprimeable 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 23 ways as a sum of consecutive naturals, for example, 333121 + ... + 333311.

It is an arithmetic number, because the mean of its divisors is an integer number (1375920).

Almost surely, 2^63644256 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 63644256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (99066240).

63644256 is an abundant number, since it is smaller than the sum of its proper divisors (134488224).

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

63644256 is a wasteful number, since it uses less digits than its factorization.

63644256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 309 (or 298 counting only the distinct ones).

The product of its digits is 103680, while the sum is 36.

The square root of 63644256 is about 7977.7350169080. The cubic root of 63644256 is about 399.2574892138.

The spelling of 63644256 in words is "sixty-three million, six hundred forty-four thousand, two hundred fifty-six".