405605489 has 2 divisors, whose sum is σ = 405605490. Its totient is φ = 405605488.

The previous prime is 405605461. The next prime is 405605491. The reversal of 405605489 is 984506504.

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., 215854864 + 189750625 = 14692^2 + 13775^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-405605489 is a prime.

Together with 405605491, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (405605419) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202802744 + 202802745.

It is an arithmetic number, because the mean of its divisors is an integer number (202802745).

Almost surely, 2^405605489 is an apocalyptic number.

It is an amenable number.

405605489 is a deficient number, since it is larger than the sum of its proper divisors (1).

405605489 is an equidigital number, since it uses as much as digits as its factorization.

405605489 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 172800, while the sum is 41.

The square root of 405605489 is about 20139.6496742123. The cubic root of 405605489 is about 740.2321459385.

The spelling of 405605489 in words is "four hundred five million, six hundred five thousand, four hundred eighty-nine".