63868640 has 72 divisors (see below), whose sum is σ = 165904200. Its totient is φ = 23217920.

The previous prime is 63868627. The next prime is 63868733. The reversal of 63868640 is 4686836.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 17711 + ... + 21009.

It is an arithmetic number, because the mean of its divisors is an integer number (2304225).

Almost surely, 2^63868640 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 63868640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82952100).

63868640 is an abundant number, since it is smaller than the sum of its proper divisors (102035560).

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

63868640 is a wasteful number, since it uses less digits than its factorization.

63868640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3336 (or 3317 counting only the distinct ones).

The product of its (nonzero) digits is 165888, while the sum is 41.

The square root of 63868640 is about 7991.7857829149. The cubic root of 63868640 is about 399.7261458859.

The spelling of 63868640 in words is "sixty-three million, eight hundred sixty-eight thousand, six hundred forty".