285716989 has 2 divisors, whose sum is σ = 285716990. Its totient is φ = 285716988.

The previous prime is 285716969. The next prime is 285717001. The reversal of 285716989 is 989617582.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 285272100 + 444889 = 16890^2 + 667^2 .

It is a cyclic number.

It is not a de Polignac number, because 285716989 - 2⁷ = 285716861 is a prime.

It is a super-2 number, since 2×285716989² = 163268395606452242, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (285716929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 142858494 + 142858495.

It is an arithmetic number, because the mean of its divisors is an integer number (142858495).

Almost surely, 2^285716989 is an apocalyptic number.

It is an amenable number.

285716989 is a deficient number, since it is larger than the sum of its proper divisors (1).

285716989 is an equidigital number, since it uses as much as digits as its factorization.

285716989 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2177280, while the sum is 55.

The square root of 285716989 is about 16903.1650586510. The cubic root of 285716989 is about 658.6358332229.

The spelling of 285716989 in words is "two hundred eighty-five million, seven hundred sixteen thousand, nine hundred eighty-nine".