1680655 has 8 divisors (see below), whose sum is σ = 2063952. Its totient is φ = 1313088.

The previous prime is 1680647. The next prime is 1680659. The reversal of 1680655 is 5560861.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1680655 - 2³ = 1680647 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1680659) 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 7 ways as a sum of consecutive naturals, for example, 3694 + ... + 4123.

It is an arithmetic number, because the mean of its divisors is an integer number (257994).

2^1680655 is an apocalyptic number.

1680655 is a deficient number, since it is larger than the sum of its proper divisors (383297).

1680655 is an equidigital number, since it uses as much as digits as its factorization.

1680655 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7865.

The product of its (nonzero) digits is 7200, while the sum is 31.

The square root of 1680655 is about 1296.4007867940. The cubic root of 1680655 is about 118.8938865276.

It can be divided in two parts, 16806 and 55, that added together give a palindrome (16861).

The spelling of 1680655 in words is "one million, six hundred eighty thousand, six hundred fifty-five".