1686636 has 96 divisors (see below), whose sum is σ = 5268480. Its totient is φ = 456192.

The previous prime is 1686631. The next prime is 1686637. The reversal of 1686636 is 6366861.

1686636 = T₃₃₃ + T₃₃₄ + ... + T₃₆₀.

1686636 is a `hidden beast` number, since 16 + 8 + 6 + 636 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 1686636.

It is not an unprimeable number, because it can be changed into a prime (1686631) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 17340 + ... + 17436.

It is an arithmetic number, because the mean of its divisors is an integer number (54880).

2^1686636 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1686636, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2634240).

1686636 is an abundant number, since it is smaller than the sum of its proper divisors (3581844).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1686636 is a wasteful number, since it uses less digits than its factorization.

1686636 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140 (or 132 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 1686636 is about 1298.7055093438. The cubic root of 1686636 is about 119.0347566954.

The spelling of 1686636 in words is "one million, six hundred eighty-six thousand, six hundred thirty-six".