216550660 has 24 divisors (see below), whose sum is σ = 455134680. Its totient is φ = 86548224.

The previous prime is 216550651. The next prime is 216550669. The reversal of 216550660 is 66055612.

It is an interprime number because it is at equal distance from previous prime (216550651) and next prime (216550669).

It can be written as a sum of positive squares in 4 ways, for example, as 17909824 + 198640836 = 4232^2 + 14094^2 .

It is not an unprimeable number, because it can be changed into a prime (216550669) 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 7 ways as a sum of consecutive naturals, for example, 24792 + ... + 32368.

It is an arithmetic number, because the mean of its divisors is an integer number (18963945).

Almost surely, 2^216550660 is an apocalyptic number.

216550660 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

216550660 is an abundant number, since it is smaller than the sum of its proper divisors (238584020).

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

216550660 is a wasteful number, since it uses less digits than its factorization.

216550660 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9015 (or 9013 counting only the distinct ones).

The product of its (nonzero) digits is 10800, while the sum is 31.

The square root of 216550660 is about 14715.6603657464. The cubic root of 216550660 is about 600.5094377033.

It can be divided in two parts, 2165 and 50660, that added together give a palindrome (52825).

The spelling of 216550660 in words is "two hundred sixteen million, five hundred fifty thousand, six hundred sixty".