1243319729 has 2 divisors, whose sum is σ = 1243319730. Its totient is φ = 1243319728.

The previous prime is 1243319719. The next prime is 1243319761. The reversal of 1243319729 is 9279133421.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1242703504 + 616225 = 35252^2 + 785^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1243319729 is a prime.

It is not a weakly prime, because it can be changed into another prime (1243319719) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 621659864 + 621659865.

It is an arithmetic number, because the mean of its divisors is an integer number (621659865).

Almost surely, 2^1243319729 is an apocalyptic number.

It is an amenable number.

1243319729 is a deficient number, since it is larger than the sum of its proper divisors (1).

1243319729 is an equidigital number, since it uses as much as digits as its factorization.

1243319729 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 81648, while the sum is 41.

The square root of 1243319729 is about 35260.7392009867. The cubic root of 1243319729 is about 1075.2949553715.

The spelling of 1243319729 in words is "one billion, two hundred forty-three million, three hundred nineteen thousand, seven hundred twenty-nine".