1680520 has 16 divisors (see below), whose sum is σ = 3781260. Its totient is φ = 672192.

The previous prime is 1680509. The next prime is 1680527. The reversal of 1680520 is 250861.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 1674436 + 6084 = 1294^2 + 78^2 .

It is a nialpdrome in base 8.

It is a junction number, because it is equal to n+sod(n) for n = 1680491 and 1680500.

It is not an unprimeable number, because it can be changed into a prime (1680527) 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, 20967 + ... + 21046.

2^1680520 is an apocalyptic number.

1680520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1680520 is an abundant number, since it is smaller than the sum of its proper divisors (2100740).

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

1680520 is a wasteful number, since it uses less digits than its factorization.

1680520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42024 (or 42020 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 22.

The square root of 1680520 is about 1296.3487185167. The cubic root of 1680520 is about 118.8907030258.

The spelling of 1680520 in words is "one million, six hundred eighty thousand, five hundred twenty".