306213220 has 12 divisors (see below), whose sum is σ = 643047804. Its totient is φ = 122485280.

The previous prime is 306213209. The next prime is 306213227. The reversal of 306213220 is 22312603.

It can be written as a sum of positive squares in 2 ways, for example, as 96079204 + 210134016 = 9802^2 + 14496^2 .

It is a super-2 number, since 2×306213220² = 187533072205536800, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (306213227) 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, 7655311 + ... + 7655350.

It is an arithmetic number, because the mean of its divisors is an integer number (53587317).

Almost surely, 2^306213220 is an apocalyptic number.

It is an amenable number.

306213220 is an abundant number, since it is smaller than the sum of its proper divisors (336834584).

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

306213220 is a wasteful number, since it uses less digits than its factorization.

306213220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15310670 (or 15310668 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 19.

The square root of 306213220 is about 17498.9491113038. The cubic root of 306213220 is about 674.0228898589.

Adding to 306213220 its reverse (22312603), we get a palindrome (328525823).

The spelling of 306213220 in words is "three hundred six million, two hundred thirteen thousand, two hundred twenty".