66220288 has 18 divisors (see below), whose sum is σ = 132182414. Its totient is φ = 33110016.

The previous prime is 66220283. The next prime is 66220291. The reversal of 66220288 is 88202266.

It can be written as a sum of positive squares in only one way, i.e., 63234304 + 2985984 = 7952^2 + 1728^2 .

It is not an unprimeable number, because it can be changed into a prime (66220283) 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 as a sum of consecutive naturals, namely, 129081 + ... + 129592.

Almost surely, 2^66220288 is an apocalyptic number.

It is an amenable number.

66220288 is a deficient number, since it is larger than the sum of its proper divisors (65962126).

66220288 is an equidigital number, since it uses as much as digits as its factorization.

66220288 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 258689 (or 258675 counting only the distinct ones).

The product of its (nonzero) digits is 18432, while the sum is 34.

The square root of 66220288 is about 8137.5848997107. The cubic root of 66220288 is about 404.5731172478.

The spelling of 66220288 in words is "sixty-six million, two hundred twenty thousand, two hundred eighty-eight".