1687994 has 32 divisors (see below), whose sum is σ = 3217536. Its totient is φ = 645120.

The previous prime is 1687991. The next prime is 1687999. The reversal of 1687994 is 4997861.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1687991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 14882 + ... + 14994.

It is an arithmetic number, because the mean of its divisors is an integer number (100548).

2^1687994 is an apocalyptic number.

1687994 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

1687994 is a deficient number, since it is larger than the sum of its proper divisors (1529542).

1687994 is a wasteful number, since it uses less digits than its factorization.

1687994 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230.

The product of its digits is 108864, while the sum is 44.

The square root of 1687994 is about 1299.2282324519. The cubic root of 1687994 is about 119.0666951882.

The spelling of 1687994 in words is "one million, six hundred eighty-seven thousand, nine hundred ninety-four".