203021221213 has 4 divisors (see below), whose sum is σ = 205302358620. Its totient is φ = 200740083808.

The previous prime is 203021221163. The next prime is 203021221231. The reversal of 203021221213 is 312122120302.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 312122120302 = 2 ⋅156061060151.

It can be written as a sum of positive squares in 2 ways, for example, as 133398066169 + 69623155044 = 365237^2 + 263862^2 .

It is a cyclic number.

It is not a de Polignac number, because 203021221213 - 2¹⁷ = 203021090141 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (203021221913) 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, 1140568570 + ... + 1140568747.

It is an arithmetic number, because the mean of its divisors is an integer number (51325589655).

Almost surely, 2^203021221213 is an apocalyptic number.

It is an amenable number.

203021221213 is a deficient number, since it is larger than the sum of its proper divisors (2281137407).

203021221213 is an equidigital number, since it uses as much as digits as its factorization.

203021221213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2281137406.

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

Adding to 203021221213 its reverse (312122120302), we get a palindrome (515143341515).

The spelling of 203021221213 in words is "two hundred three billion, twenty-one million, two hundred twenty-one thousand, two hundred thirteen".