100047581 has 4 divisors (see below), whose sum is σ = 100484700. Its totient is φ = 99610464.

The previous prime is 100047553. The next prime is 100047587. The reversal of 100047581 is 185740001.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 65060356 + 34987225 = 8066^2 + 5915^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-100047581 is a prime.

It is a super-2 number, since 2×100047581² = 20019036927903122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 100047581.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (100047587) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 218216 + ... + 218673.

It is an arithmetic number, because the mean of its divisors is an integer number (25121175).

Almost surely, 2^100047581 is an apocalyptic number.

It is an amenable number.

100047581 is a deficient number, since it is larger than the sum of its proper divisors (437119).

100047581 is an equidigital number, since it uses as much as digits as its factorization.

100047581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 437118.

The product of its (nonzero) digits is 1120, while the sum is 26.

The square root of 100047581 is about 10002.3787670734. The cubic root of 100047581 is about 464.2324888345.

Adding to 100047581 its reverse (185740001), we get a palindrome (285787582).

The spelling of 100047581 in words is "one hundred million, forty-seven thousand, five hundred eighty-one".