105555581 has 2 divisors, whose sum is σ = 105555582. Its totient is φ = 105555580.

The previous prime is 105555557. The next prime is 105555587. The reversal of 105555581 is 185555501.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 53787556 + 51768025 = 7334^2 + 7195^2 .

It is a cyclic number.

It is not a de Polignac number, because 105555581 - 2¹⁴ = 105539197 is a prime.

It is a super-2 number, since 2×105555581² = 22283961360495122, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (105555587) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 52777790 + 52777791.

It is an arithmetic number, because the mean of its divisors is an integer number (52777791).

Almost surely, 2^105555581 is an apocalyptic number.

It is an amenable number.

105555581 is a deficient number, since it is larger than the sum of its proper divisors (1).

105555581 is an equidigital number, since it uses as much as digits as its factorization.

105555581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 25000, while the sum is 35.

The square root of 105555581 is about 10274.0245765717. The cubic root of 105555581 is about 472.6000176464.

The spelling of 105555581 in words is "one hundred five million, five hundred fifty-five thousand, five hundred eighty-one".