1985605 has 8 divisors (see below), whose sum is σ = 2447352. Its totient is φ = 1545408.

The previous prime is 1985593. The next prime is 1985623. The reversal of 1985605 is 5065891.

It can be written as a sum of positive squares in 4 ways, for example, as 173889 + 1811716 = 417^2 + 1346^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1985605 - 2⁵ = 1985573 is a prime.

It is a Duffinian number.

1985605 is a lucky number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5182 + ... + 5551.

It is an arithmetic number, because the mean of its divisors is an integer number (305919).

2^1985605 is an apocalyptic number.

It is an amenable number.

1985605 is a deficient number, since it is larger than the sum of its proper divisors (461747).

1985605 is a wasteful number, since it uses less digits than its factorization.

1985605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10775.

The product of its (nonzero) digits is 10800, while the sum is 34.

The square root of 1985605 is about 1409.1149704691. The cubic root of 1985605 is about 125.6891008065.

The spelling of 1985605 in words is "one million, nine hundred eighty-five thousand, six hundred five".