66333220 has 12 divisors (see below), whose sum is σ = 139299804. Its totient is φ = 26533280.

The previous prime is 66333209. The next prime is 66333221. The reversal of 66333220 is 2233366.

It can be written as a sum of positive squares in 2 ways, for example, as 33431524 + 32901696 = 5782^2 + 5736^2 .

It is a nialpdrome in base 10.

It is not an unprimeable number, because it can be changed into a prime (66333221) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1658311 + ... + 1658350.

It is an arithmetic number, because the mean of its divisors is an integer number (11608317).

Almost surely, 2^66333220 is an apocalyptic number.

It is an amenable number.

66333220 is an abundant number, since it is smaller than the sum of its proper divisors (72966584).

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

66333220 is a wasteful number, since it uses less digits than its factorization.

66333220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3316670 (or 3316668 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 25.

The square root of 66333220 is about 8144.5208576073. The cubic root of 66333220 is about 404.8029728023.

Adding to 66333220 its reverse (2233366), we get a palindrome (68566586).

The spelling of 66333220 in words is "sixty-six million, three hundred thirty-three thousand, two hundred twenty".