216805560 has 32 divisors (see below), whose sum is σ = 650417040. Its totient is φ = 57814784.

The previous prime is 216805541. The next prime is 216805571. The reversal of 216805560 is 65508612.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 903237 + ... + 903476.

Almost surely, 2^216805560 is an apocalyptic number.

216805560 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216805560 is an abundant number, since it is smaller than the sum of its proper divisors (433611480).

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

216805560 is a wasteful number, since it uses less digits than its factorization.

216805560 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1806727 (or 1806723 counting only the distinct ones).

The product of its (nonzero) digits is 14400, while the sum is 33.

The square root of 216805560 is about 14724.3186599584. The cubic root of 216805560 is about 600.7449635549.

The spelling of 216805560 in words is "two hundred sixteen million, eight hundred five thousand, five hundred sixty".