63865536 has 224 divisors, whose sum is σ = 211653120. Its totient is φ = 16588800.

The previous prime is 63865531. The next prime is 63865547. The reversal of 63865536 is 63556836.

It is a tau number, because it is divible by the number of its divisors (224).

It is a super-3 number, since 3×63865536³ (a number of 24 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (63865531) by changing a digit.

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 31 ways as a sum of consecutive naturals, for example, 1046946 + ... + 1047006.

It is an arithmetic number, because the mean of its divisors is an integer number (944880).

Almost surely, 2^63865536 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 63865536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (105826560).

63865536 is an abundant number, since it is smaller than the sum of its proper divisors (147787584).

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

63865536 is a wasteful number, since it uses less digits than its factorization.

63865536 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 143 (or 133 counting only the distinct ones).

The product of its digits is 388800, while the sum is 42.

The square root of 63865536 is about 7991.5915811558. The cubic root of 63865536 is about 399.7196702506.

The spelling of 63865536 in words is "sixty-three million, eight hundred sixty-five thousand, five hundred thirty-six".