1680505566 has 16 divisors (see below), whose sum is σ = 3370377600. Its totient is φ = 558607448.

The previous prime is 1680505523. The next prime is 1680505579. The reversal of 1680505566 is 6655050861.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 387936 + ... + 392243.

It is an arithmetic number, because the mean of its divisors is an integer number (210648600).

Almost surely, 2^1680505566 is an apocalyptic number.

1680505566 is an abundant number, since it is smaller than the sum of its proper divisors (1689872034).

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

1680505566 is a wasteful number, since it uses less digits than its factorization.

1680505566 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 780543.

The product of its (nonzero) digits is 216000, while the sum is 42.

The square root of 1680505566 is about 40993.9698736290. The cubic root of 1680505566 is about 1188.9036264041.

The spelling of 1680505566 in words is "one billion, six hundred eighty million, five hundred five thousand, five hundred sixty-six".