213223201021 has 4 divisors (see below), whose sum is σ = 213224478844. Its totient is φ = 213221923200.

The previous prime is 213223201001. The next prime is 213223201027. The reversal of 213223201021 is 120102322312.

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 119823284025 + 93399916996 = 346155^2 + 305614^2 .

It is a cyclic number.

It is not a de Polignac number, because 213223201021 - 2⁵ = 213223200989 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 213223201021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213223201027) 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, 342900 + ... + 737581.

It is an arithmetic number, because the mean of its divisors is an integer number (53306119711).

Almost surely, 2^213223201021 is an apocalyptic number.

It is an amenable number.

213223201021 is a deficient number, since it is larger than the sum of its proper divisors (1277823).

213223201021 is a wasteful number, since it uses less digits than its factorization.

213223201021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1277822.

The product of its (nonzero) digits is 288, while the sum is 19.

Adding to 213223201021 its reverse (120102322312), we get a palindrome (333325523333).

The spelling of 213223201021 in words is "two hundred thirteen billion, two hundred twenty-three million, two hundred one thousand, twenty-one".