213221329 has 4 divisors (see below), whose sum is σ = 214136676. Its totient is φ = 212305984.

The previous prime is 213221251. The next prime is 213221377. The reversal of 213221329 is 923122312.

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 72846225 + 140375104 = 8535^2 + 11848^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-213221329 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213221389) 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, 457324 + ... + 457789.

It is an arithmetic number, because the mean of its divisors is an integer number (53534169).

Almost surely, 2^213221329 is an apocalyptic number.

It is an amenable number.

213221329 is a deficient number, since it is larger than the sum of its proper divisors (915347).

213221329 is an equidigital number, since it uses as much as digits as its factorization.

213221329 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 915346.

The product of its digits is 1296, while the sum is 25.

The square root of 213221329 is about 14602.1001571692. The cubic root of 213221329 is about 597.4160444120.

The spelling of 213221329 in words is "two hundred thirteen million, two hundred twenty-one thousand, three hundred twenty-nine".