243121213403 has 16 divisors (see below), whose sum is σ = 259215818400. Its totient is φ = 227364952320.

The previous prime is 243121213373. The next prime is 243121213499. The reversal of 243121213403 is 304312121342.

It is a cyclic number.

It is not a de Polignac number, because 243121213403 - 2⁶ = 243121213339 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (243121213703) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 919313 + ... + 1153853.

It is an arithmetic number, because the mean of its divisors is an integer number (16200988650).

Almost surely, 2^243121213403 is an apocalyptic number.

243121213403 is a deficient number, since it is larger than the sum of its proper divisors (16094604997).

243121213403 is a wasteful number, since it uses less digits than its factorization.

243121213403 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 235262.

The product of its (nonzero) digits is 3456, while the sum is 26.

Adding to 243121213403 its reverse (304312121342), we get a palindrome (547433334745).

The spelling of 243121213403 in words is "two hundred forty-three billion, one hundred twenty-one million, two hundred thirteen thousand, four hundred three".