105806021 has 2 divisors, whose sum is σ = 105806022. Its totient is φ = 105806020.

The previous prime is 105805979. The next prime is 105806033. The reversal of 105806021 is 120608501.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 105801796 + 4225 = 10286^2 + 65^2 .

It is a cyclic number.

It is not a de Polignac number, because 105806021 - 2¹⁴ = 105789637 is a prime.

It is a super-2 number, since 2×105806021² = 22389828159704882, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (105806321) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 52903010 + 52903011.

It is an arithmetic number, because the mean of its divisors is an integer number (52903011).

Almost surely, 2^105806021 is an apocalyptic number.

It is an amenable number.

105806021 is a deficient number, since it is larger than the sum of its proper divisors (1).

105806021 is an equidigital number, since it uses as much as digits as its factorization.

105806021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 480, while the sum is 23.

The square root of 105806021 is about 10286.2053741893. The cubic root of 105806021 is about 472.9734842933.

The spelling of 105806021 in words is "one hundred five million, eight hundred six thousand, twenty-one".