1687385 has 16 divisors (see below), whose sum is σ = 2378496. Its totient is φ = 1124928.

The previous prime is 1687381. The next prime is 1687393. The reversal of 1687385 is 5837861.

It is not a de Polignac number, because 1687385 - 2² = 1687381 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1687381) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 644 + ... + 1946.

It is an arithmetic number, because the mean of its divisors is an integer number (148656).

2^1687385 is an apocalyptic number.

It is an amenable number.

1687385 is a deficient number, since it is larger than the sum of its proper divisors (691111).

1687385 is a wasteful number, since it uses less digits than its factorization.

1687385 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1352.

The product of its digits is 40320, while the sum is 38.

The square root of 1687385 is about 1298.9938414019. The cubic root of 1687385 is about 119.0523743751.

The spelling of 1687385 in words is "one million, six hundred eighty-seven thousand, three hundred eighty-five".