63581 has 8 divisors (see below), whose sum is σ = 75264. Its totient is φ = 52560.

The previous prime is 63577. The next prime is 63587. The reversal of 63581 is 18536.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 63581 - 2² = 63577 is a prime.

It is a super-2 number, since 2×63581² = 8085087122, which contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (63587) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 71 + ... + 363.

It is an arithmetic number, because the mean of its divisors is an integer number (9408).

2⁶³⁵⁸¹ is an apocalyptic number.

It is an amenable number.

63581 is a deficient number, since it is larger than the sum of its proper divisors (11683).

63581 is a wasteful number, since it uses less digits than its factorization.

63581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 331.

The product of its digits is 720, while the sum is 23.

The square root of 63581 is about 252.1527314942. The cubic root of 63581 is about 39.9125171416.

The spelling of 63581 in words is "sixty-three thousand, five hundred eighty-one".