203113121 has 4 divisors (see below), whose sum is σ = 205124244. Its totient is φ = 201102000.

The previous prime is 203113111. The next prime is 203113133. The reversal of 203113121 is 121311302.

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 151560721 + 51552400 = 12311^2 + 7180^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-203113121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 203113096 and 203113105.

It is not an unprimeable number, because it can be changed into a prime (203113111) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1005410 + ... + 1005611.

It is an arithmetic number, because the mean of its divisors is an integer number (51281061).

Almost surely, 2^203113121 is an apocalyptic number.

It is an amenable number.

203113121 is a deficient number, since it is larger than the sum of its proper divisors (2011123).

203113121 is a wasteful number, since it uses less digits than its factorization.

203113121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2011122.

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 203113121 is about 14251.7760647577. The cubic root of 203113121 is about 587.8222126279.

Adding to 203113121 its reverse (121311302), we get a palindrome (324424423).

It can be divided in two parts, 20311 and 3121, that added together give a palindrome (23432).

The spelling of 203113121 in words is "two hundred three million, one hundred thirteen thousand, one hundred twenty-one".