1243123121 has 8 divisors (see below), whose sum is σ = 1260977760. Its totient is φ = 1225337152.

The previous prime is 1243123103. The next prime is 1243123187. The reversal of 1243123121 is 1213213421.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1243123121 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1243123093 and 1243123102.

It is not an unprimeable number, because it can be changed into a prime (1243173121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19865 + ... + 53673.

It is an arithmetic number, because the mean of its divisors is an integer number (157622220).

Almost surely, 2^1243123121 is an apocalyptic number.

It is an amenable number.

1243123121 is a deficient number, since it is larger than the sum of its proper divisors (17854639).

1243123121 is an equidigital number, since it uses as much as digits as its factorization.

1243123121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34335.

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

The square root of 1243123121 is about 35257.9511741678. The cubic root of 1243123121 is about 1075.2382730529.

Adding to 1243123121 its reverse (1213213421), we get a palindrome (2456336542).

The spelling of 1243123121 in words is "one billion, two hundred forty-three million, one hundred twenty-three thousand, one hundred twenty-one".