405809101 has 2 divisors, whose sum is σ = 405809102. Its totient is φ = 405809100.

The previous prime is 405809039. The next prime is 405809119. The reversal of 405809101 is 101908504.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 279224100 + 126585001 = 16710^2 + 11251^2 .

It is a cyclic number.

It is not a de Polignac number, because 405809101 - 2⁹ = 405808589 is a prime.

It is equal to p_21629431 and since 405809101 and 21629431 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 405809101.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (405809191) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202904550 + 202904551.

It is an arithmetic number, because the mean of its divisors is an integer number (202904551).

Almost surely, 2^405809101 is an apocalyptic number.

It is an amenable number.

405809101 is a deficient number, since it is larger than the sum of its proper divisors (1).

405809101 is an equidigital number, since it uses as much as digits as its factorization.

405809101 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440, while the sum is 28.

The square root of 405809101 is about 20144.7040434949. The cubic root of 405809101 is about 740.3559895407.

The spelling of 405809101 in words is "four hundred five million, eight hundred nine thousand, one hundred one".