405500561 has 2 divisors, whose sum is σ = 405500562. Its totient is φ = 405500560.

The previous prime is 405500551. The next prime is 405500587. The reversal of 405500561 is 165005504.

It is an a-pointer prime, because the next prime (405500587) can be obtained adding 405500561 to its sum of digits (26).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 376942225 + 28558336 = 19415^2 + 5344^2 .

It is a cyclic number.

It is not a de Polignac number, because 405500561 - 2¹⁰ = 405499537 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 405500561.

It is not a weakly prime, because it can be changed into another prime (405500521) 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, 202750280 + 202750281.

It is an arithmetic number, because the mean of its divisors is an integer number (202750281).

Almost surely, 2^405500561 is an apocalyptic number.

It is an amenable number.

405500561 is a deficient number, since it is larger than the sum of its proper divisors (1).

405500561 is an equidigital number, since it uses as much as digits as its factorization.

405500561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3000, while the sum is 26.

The square root of 405500561 is about 20137.0444951587. The cubic root of 405500561 is about 740.1683090499.

The spelling of 405500561 in words is "four hundred five million, five hundred thousand, five hundred sixty-one".