203404343421221 has 4 divisors (see below), whose sum is σ = 203406334151244. Its totient is φ = 203402352691200.

The previous prime is 203404343421157. The next prime is 203404343421239. The reversal of 203404343421221 is 122124343404302.

It is a happy number.

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 82481089248100 + 120923254173121 = 9081910^2 + 10996511^2 .

It is a cyclic number.

It is not a de Polignac number, because 203404343421221 - 2⁶ = 203404343421157 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 (203404343421241) 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, 995211740 + ... + 995416101.

It is an arithmetic number, because the mean of its divisors is an integer number (50851583537811).

Almost surely, 2^{203404343421221} is an apocalyptic number.

It is an amenable number.

203404343421221 is a deficient number, since it is larger than the sum of its proper divisors (1990730023).

203404343421221 is a wasteful number, since it uses less digits than its factorization.

203404343421221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1990730022.

The product of its (nonzero) digits is 110592, while the sum is 35.

Adding to 203404343421221 its reverse (122124343404302), we get a palindrome (325528686825523).

The spelling of 203404343421221 in words is "two hundred three trillion, four hundred four billion, three hundred forty-three million, four hundred twenty-one thousand, two hundred twenty-one".