213223121 has 8 divisors (see below), whose sum is σ = 216951144. Its totient is φ = 209502720.

The previous prime is 213223117. The next prime is 213223123. The reversal of 213223121 is 121322312.

213223121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 13424896 + 199798225 = 3664^2 + 14135^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 213223121 - 2² = 213223117 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 213223121.

It is not an unprimeable number, because it can be changed into a prime (213223123) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 104705 + ... + 106721.

It is an arithmetic number, because the mean of its divisors is an integer number (27118893).

Almost surely, 2^213223121 is an apocalyptic number.

It is an amenable number.

213223121 is a deficient number, since it is larger than the sum of its proper divisors (3728023).

213223121 is a wasteful number, since it uses less digits than its factorization.

213223121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3811.

The product of its digits is 144, while the sum is 17.

The square root of 213223121 is about 14602.1615180767. The cubic root of 213223121 is about 597.4177180509.

Adding to 213223121 its reverse (121322312), we get a palindrome (334545433).

The spelling of 213223121 in words is "two hundred thirteen million, two hundred twenty-three thousand, one hundred twenty-one".