213000305 has 24 divisors (see below), whose sum is σ = 305380008. Its totient is φ = 142103808.

The previous prime is 213000301. The next prime is 213000311. The reversal of 213000305 is 503000312.

It can be written as a sum of positive squares in 4 ways, for example, as 89434849 + 123565456 = 9457^2 + 11116^2 .

It is not a de Polignac number, because 213000305 - 2² = 213000301 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 213000305.

It is not an unprimeable number, because it can be changed into a prime (213000301) 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 23 ways as a sum of consecutive naturals, for example, 2684 + ... + 20813.

It is an arithmetic number, because the mean of its divisors is an integer number (12724167).

Almost surely, 2^213000305 is an apocalyptic number.

It is an amenable number.

213000305 is a deficient number, since it is larger than the sum of its proper divisors (92379703).

213000305 is a wasteful number, since it uses less digits than its factorization.

213000305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23553 (or 23546 counting only the distinct ones).

The product of its (nonzero) digits is 90, while the sum is 14.

The square root of 213000305 is about 14594.5299684505. The cubic root of 213000305 is about 597.2095470354.

Adding to 213000305 its reverse (503000312), we get a palindrome (716000617).

The spelling of 213000305 in words is "two hundred thirteen million, three hundred five", and thus it is an aban number.