63781520 has 80 divisors (see below), whose sum is σ = 163382400. Its totient is φ = 23154560.

The previous prime is 63781517. The next prime is 63781541. The reversal of 63781520 is 2518736.

It is a happy number.

63781520 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (80).

It is a hoax number, since the sum of its digits (32) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 106181 + ... + 106779.

It is an arithmetic number, because the mean of its divisors is an integer number (2042280).

Almost surely, 2^63781520 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 63781520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (81691200).

63781520 is an abundant number, since it is smaller than the sum of its proper divisors (99600880).

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

63781520 is a wasteful number, since it uses less digits than its factorization.

63781520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 645 (or 617 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 63781520 is about 7986.3333263770. Note that the first 4 decimals coincide. The cubic root of 63781520 is about 399.5443144071.

The spelling of 63781520 in words is "sixty-three million, seven hundred eighty-one thousand, five hundred twenty".