405388561 has 2 divisors, whose sum is σ = 405388562. Its totient is φ = 405388560.

The previous prime is 405388531. The next prime is 405388589. The reversal of 405388561 is 165883504.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 389825536 + 15563025 = 19744^2 + 3945^2 .

It is a cyclic number.

It is not a de Polignac number, because 405388561 - 2⁷ = 405388433 is a prime.

It is not a weakly prime, because it can be changed into another prime (405388531) 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, 202694280 + 202694281.

It is an arithmetic number, because the mean of its divisors is an integer number (202694281).

Almost surely, 2^405388561 is an apocalyptic number.

It is an amenable number.

405388561 is a deficient number, since it is larger than the sum of its proper divisors (1).

405388561 is an equidigital number, since it uses as much as digits as its factorization.

405388561 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 115200, while the sum is 40.

The square root of 405388561 is about 20134.2633587623. The cubic root of 405388561 is about 740.1001574927.

The spelling of 405388561 in words is "four hundred five million, three hundred eighty-eight thousand, five hundred sixty-one".