213012321 has 16 divisors (see below), whose sum is σ = 288571584. Its totient is φ = 139739904.

The previous prime is 213012313. The next prime is 213012323. The reversal of 213012321 is 123210312.

213012321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 213012321 - 2³ = 213012313 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 213012321.

It is not an unprimeable number, because it can be changed into a prime (213012323) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 127725 + ... + 129381.

It is an arithmetic number, because the mean of its divisors is an integer number (18035724).

Almost surely, 2^213012321 is an apocalyptic number.

It is an amenable number.

213012321 is a deficient number, since it is larger than the sum of its proper divisors (75559263).

213012321 is a wasteful number, since it uses less digits than its factorization.

213012321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2320.

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 213012321 is about 14594.9416237270. The cubic root of 213012321 is about 597.2207769646.

Adding to 213012321 its reverse (123210312), we get a palindrome (336222633).

The spelling of 213012321 in words is "two hundred thirteen million, twelve thousand, three hundred twenty-one".