1686331 has 4 divisors (see below), whose sum is σ = 1725592. Its totient is φ = 1647072.

The previous prime is 1686329. The next prime is 1686341. The reversal of 1686331 is 1336861.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1686331 - 2¹ = 1686329 is a prime.

It is a super-2 number, since 2×1686331² = 5687424483122, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1686331.

It is not an unprimeable number, because it can be changed into a prime (1686341) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 19566 + ... + 19651.

It is an arithmetic number, because the mean of its divisors is an integer number (431398).

2^1686331 is an apocalyptic number.

1686331 is a deficient number, since it is larger than the sum of its proper divisors (39261).

1686331 is an equidigital number, since it uses as much as digits as its factorization.

1686331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39260.

The product of its digits is 2592, while the sum is 28.

The square root of 1686331 is about 1298.5880794155. The cubic root of 1686331 is about 119.0275811125.

It can be divided in two parts, 16863 and 31, that multiplied together give a triangular number (522753 = T₁₀₂₂).

The spelling of 1686331 in words is "one million, six hundred eighty-six thousand, three hundred thirty-one".