1681816 has 16 divisors (see below), whose sum is σ = 3227400. Its totient is φ = 821184.

The previous prime is 1681807. The next prime is 1681817. The reversal of 1681816 is 6181861.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1681817) 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, 2101 + ... + 2788.

2^1681816 is an apocalyptic number.

It is an amenable number.

1681816 is a deficient number, since it is larger than the sum of its proper divisors (1545584).

1681816 is a wasteful number, since it uses less digits than its factorization.

1681816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4938 (or 4934 counting only the distinct ones).

The product of its digits is 2304, while the sum is 31.

The square root of 1681816 is about 1296.8484876808. The cubic root of 1681816 is about 118.9212576079.

The spelling of 1681816 in words is "one million, six hundred eighty-one thousand, eight hundred sixteen".