729638123 has 2 divisors, whose sum is σ = 729638124. Its totient is φ = 729638122.

The previous prime is 729638111. The next prime is 729638149. The reversal of 729638123 is 321836927.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 729638123 - 2¹⁰ = 729637099 is a prime.

It is an alternating number because its digits alternate between odd and even.

It is not a weakly prime, because it can be changed into another prime (729638153) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 364819061 + 364819062.

It is an arithmetic number, because the mean of its divisors is an integer number (364819062).

Almost surely, 2^729638123 is an apocalyptic number.

729638123 is a deficient number, since it is larger than the sum of its proper divisors (1).

729638123 is an equidigital number, since it uses as much as digits as its factorization.

729638123 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 41.

The square root of 729638123 is about 27011.8145077298. The cubic root of 729638123 is about 900.2625254728.

The spelling of 729638123 in words is "seven hundred twenty-nine million, six hundred thirty-eight thousand, one hundred twenty-three".