1243312129 has 8 divisors (see below), whose sum is σ = 1263516552. Its totient is φ = 1223193600.

The previous prime is 1243312069. The next prime is 1243312163. The reversal of 1243312129 is 9212133421.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 382007025 + 861305104 = 19545^2 + 29348^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 1243312129 - 2²⁵ = 1209757697 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1243312097 and 1243312106.

It is not an unprimeable number, because it can be changed into a prime (1243312199) 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 7 ways as a sum of consecutive naturals, for example, 8037 + ... + 50509.

It is an arithmetic number, because the mean of its divisors is an integer number (157939569).

Almost surely, 2^1243312129 is an apocalyptic number.

It is an amenable number.

1243312129 is a deficient number, since it is larger than the sum of its proper divisors (20204423).

1243312129 is an equidigital number, since it uses as much as digits as its factorization.

1243312129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42947.

The product of its digits is 2592, while the sum is 28.

The square root of 1243312129 is about 35260.6314322362. The cubic root of 1243312129 is about 1075.2927643936.

The spelling of 1243312129 in words is "one billion, two hundred forty-three million, three hundred twelve thousand, one hundred twenty-nine".