405894989 has 2 divisors, whose sum is σ = 405894990. Its totient is φ = 405894988.

The previous prime is 405894953. The next prime is 405895033. The reversal of 405894989 is 989498504.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 336722500 + 69172489 = 18350^2 + 8317^2 .

It is a cyclic number.

It is not a de Polignac number, because 405894989 - 2⁸ = 405894733 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (405894919) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 202947494 + 202947495.

It is an arithmetic number, because the mean of its divisors is an integer number (202947495).

Almost surely, 2^405894989 is an apocalyptic number.

It is an amenable number.

405894989 is a deficient number, since it is larger than the sum of its proper divisors (1).

405894989 is an equidigital number, since it uses as much as digits as its factorization.

405894989 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3732480, while the sum is 56.

The square root of 405894989 is about 20146.8357068796. The cubic root of 405894989 is about 740.4082170615.

The spelling of 405894989 in words is "four hundred five million, eight hundred ninety-four thousand, nine hundred eighty-nine".