1663865660 has 12 divisors (see below), whose sum is σ = 3494117928. Its totient is φ = 665546256.

The previous prime is 1663865653. The next prime is 1663865711. The reversal of 1663865660 is 665683661.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41596622 + ... + 41596661.

It is an arithmetic number, because the mean of its divisors is an integer number (291176494).

Almost surely, 2^1663865660 is an apocalyptic number.

1663865660 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1663865660 is an abundant number, since it is smaller than the sum of its proper divisors (1830252268).

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

1663865660 is a wasteful number, since it uses less digits than its factorization.

1663865660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 83193292 (or 83193290 counting only the distinct ones).

The product of its (nonzero) digits is 933120, while the sum is 47.

The square root of 1663865660 is about 40790.5094354067. The cubic root of 1663865660 is about 1184.9665369437.

The spelling of 1663865660 in words is "one billion, six hundred sixty-three million, eight hundred sixty-five thousand, six hundred sixty".