20343112121 has 4 divisors (see below), whose sum is σ = 20343542244. Its totient is φ = 20342682000.

The previous prime is 20343112099. The next prime is 20343112123. The reversal of 20343112121 is 12121134302.

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 8129546896 + 12213565225 = 90164^2 + 110515^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20343112121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20343112093 and 20343112102.

It is not an unprimeable number, because it can be changed into a prime (20343112123) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 133910 + ... + 242111.

It is an arithmetic number, because the mean of its divisors is an integer number (5085885561).

Almost surely, 2^20343112121 is an apocalyptic number.

It is an amenable number.

20343112121 is a deficient number, since it is larger than the sum of its proper divisors (430123).

20343112121 is an equidigital number, since it uses as much as digits as its factorization.

20343112121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 430122.

The product of its (nonzero) digits is 288, while the sum is 20.

Adding to 20343112121 its reverse (12121134302), we get a palindrome (32464246423).

The spelling of 20343112121 in words is "twenty billion, three hundred forty-three million, one hundred twelve thousand, one hundred twenty-one".