1509985 has 4 divisors (see below), whose sum is σ = 1811988. Its totient is φ = 1207984.

The previous prime is 1509971. The next prime is 1509997. The reversal of 1509985 is 5899051.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 5899051 = 17 ⋅347003.

It can be written as a sum of positive squares in 2 ways, for example, as 345744 + 1164241 = 588^2 + 1079^2 .

It is a cyclic number.

It is not a de Polignac number, because 1509985 - 2⁵ = 1509953 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 150994 + ... + 151003.

It is an arithmetic number, because the mean of its divisors is an integer number (452997).

2^1509985 is an apocalyptic number.

It is an amenable number.

1509985 is a deficient number, since it is larger than the sum of its proper divisors (302003).

1509985 is an equidigital number, since it uses as much as digits as its factorization.

1509985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 302002.

The product of its (nonzero) digits is 16200, while the sum is 37.

The square root of 1509985 is about 1228.8144693159. The cubic root of 1509985 is about 114.7248621054.

The spelling of 1509985 in words is "one million, five hundred nine thousand, nine hundred eighty-five".