1680404560 has 20 divisors (see below), whose sum is σ = 3906940788. Its totient is φ = 672161792.

The previous prime is 1680404549. The next prime is 1680404563. The reversal of 1680404560 is 654040861.

It can be written as a sum of positive squares in 2 ways, for example, as 1095345216 + 585059344 = 33096^2 + 24188^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1680404563) 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 3 ways as a sum of consecutive naturals, for example, 10502449 + ... + 10502608.

Almost surely, 2^1680404560 is an apocalyptic number.

1680404560 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1680404560 is an abundant number, since it is smaller than the sum of its proper divisors (2226536228).

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

1680404560 is a wasteful number, since it uses less digits than its factorization.

1680404560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21005070 (or 21005064 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 34.

The square root of 1680404560 is about 40992.7378934367. The cubic root of 1680404560 is about 1188.8798064284.

The spelling of 1680404560 in words is "one billion, six hundred eighty million, four hundred four thousand, five hundred sixty".