409987 has 2 divisors, whose sum is σ = 409988. Its totient is φ = 409986.

The previous prime is 409967. The next prime is 409993. The reversal of 409987 is 789904.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 409987 - 2¹⁵ = 377219 is a prime.

It is a super-3 number, since 3×409987³ = 206743332923603409, which contains 333 as substring.

409987 is a lucky number.

It is not a weakly prime, because it can be changed into another prime (409967) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 204993 + 204994.

It is an arithmetic number, because the mean of its divisors is an integer number (204994).

2⁴⁰⁹⁹⁸⁷ is an apocalyptic number.

409987 is a deficient number, since it is larger than the sum of its proper divisors (1).

409987 is an equidigital number, since it uses as much as digits as its factorization.

409987 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 18144, while the sum is 37.

The square root of 409987 is about 640.3022723683. The cubic root of 409987 is about 74.2888032317.

It can be divided in two parts, 4099 and 87, that added together give a triangular number (4186 = T₉₁).

The spelling of 409987 in words is "four hundred nine thousand, nine hundred eighty-seven".