213204021 has 8 divisors (see below), whose sum is σ = 300993984. Its totient is φ = 133775040.

The previous prime is 213204007. The next prime is 213204037. The reversal of 213204021 is 120402312.

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

It is a de Polignac number, because none of the positive numbers 2^k-213204021 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213204041) 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, 2090185 + ... + 2090286.

It is an arithmetic number, because the mean of its divisors is an integer number (37624248).

Almost surely, 2^213204021 is an apocalyptic number.

It is an amenable number.

213204021 is a deficient number, since it is larger than the sum of its proper divisors (87789963).

213204021 is a wasteful number, since it uses less digits than its factorization.

213204021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4180491.

The product of its (nonzero) digits is 96, while the sum is 15.

The square root of 213204021 is about 14601.5074906668. The cubic root of 213204021 is about 597.3998791176.

Adding to 213204021 its reverse (120402312), we get a palindrome (333606333).

The spelling of 213204021 in words is "two hundred thirteen million, two hundred four thousand, twenty-one".