213133321 has 4 divisors (see below), whose sum is σ = 213175444. Its totient is φ = 213091200.

The previous prime is 213133313. The next prime is 213133337. The reversal of 213133321 is 123331312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 71166096 + 141967225 = 8436^2 + 11915^2 .

It is a cyclic number.

It is not a de Polignac number, because 213133321 - 2³ = 213133313 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213133351) 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, 12240 + ... + 24001.

It is an arithmetic number, because the mean of its divisors is an integer number (53293861).

Almost surely, 2^213133321 is an apocalyptic number.

It is an amenable number.

213133321 is a deficient number, since it is larger than the sum of its proper divisors (42123).

213133321 is an equidigital number, since it uses as much as digits as its factorization.

213133321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42122.

The product of its digits is 324, while the sum is 19.

The square root of 213133321 is about 14599.0863070262. The cubic root of 213133321 is about 597.3338377726. Note that the first 3 decimals are identical.

Adding to 213133321 its reverse (123331312), we get a palindrome (336464633).

The spelling of 213133321 in words is "two hundred thirteen million, one hundred thirty-three thousand, three hundred twenty-one".