203211312121 has 4 divisors (see below), whose sum is σ = 203267189092. Its totient is φ = 203155435152.

The previous prime is 203211312023. The next prime is 203211312131. The reversal of 203211312121 is 121213112302.

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 1448639721 + 201762672400 = 38061^2 + 449180^2 .

It is a cyclic number.

It is not a de Polignac number, because 203211312121 - 2⁷ = 203211311993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (203211312131) 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, 27933030 + ... + 27940303.

It is an arithmetic number, because the mean of its divisors is an integer number (50816797273).

Almost surely, 2^203211312121 is an apocalyptic number.

It is an amenable number.

203211312121 is a deficient number, since it is larger than the sum of its proper divisors (55876971).

203211312121 is an equidigital number, since it uses as much as digits as its factorization.

203211312121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55876970.

The product of its (nonzero) digits is 144, while the sum is 19.

Adding to 203211312121 its reverse (121213112302), we get a palindrome (324424424423).

The spelling of 203211312121 in words is "two hundred three billion, two hundred eleven million, three hundred twelve thousand, one hundred twenty-one".