100581 has 8 divisors (see below), whose sum is σ = 144480. Its totient is φ = 61872.

The previous prime is 100559. The next prime is 100591. The reversal of 100581 is 185001.

It is a happy number.

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

It is not a de Polignac number, because 100581 - 2⁵ = 100549 is a prime.

It is a super-2 number, since 2×100581² = 20233075122, which contains 22 as substring.

It is a Curzon number.

100581 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 100581.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 100581.

It is not an unprimeable number, because it can be changed into a prime (100501) 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, 1251 + ... + 1328.

It is an arithmetic number, because the mean of its divisors is an integer number (18060).

2¹⁰⁰⁵⁸¹ is an apocalyptic number.

It is an amenable number.

100581 is a deficient number, since it is larger than the sum of its proper divisors (43899).

100581 is a wasteful number, since it uses less digits than its factorization.

100581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2595.

The product of its (nonzero) digits is 40, while the sum is 15.

The square root of 100581 is about 317.1450772123. The cubic root of 100581 is about 46.5056069086.

Adding to 100581 its reverse (185001), we get a palindrome (285582).

The spelling of 100581 in words is "one hundred thousand, five hundred eighty-one".