1236728305 has 8 divisors (see below), whose sum is σ = 1520271144. Its totient is φ = 965251200.

The previous prime is 1236728281. The next prime is 1236728309. The reversal of 1236728305 is 5038276321.

It can be written as a sum of positive squares in 4 ways, for example, as 118026496 + 1118701809 = 10864^2 + 33447^2 .

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

It is not a de Polignac number, because 1236728305 - 2⁷ = 1236728177 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1236728309) 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 in 7 ways as a sum of consecutive naturals, for example, 3016206 + ... + 3016615.

It is an arithmetic number, because the mean of its divisors is an integer number (190033893).

Almost surely, 2^1236728305 is an apocalyptic number.

It is an amenable number.

1236728305 is a deficient number, since it is larger than the sum of its proper divisors (283542839).

1236728305 is an equidigital number, since it uses as much as digits as its factorization.

1236728305 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6032867.

The product of its (nonzero) digits is 60480, while the sum is 37.

The square root of 1236728305 is about 35167.1480930712. The cubic root of 1236728305 is about 1073.3913723122.

The spelling of 1236728305 in words is "one billion, two hundred thirty-six million, seven hundred twenty-eight thousand, three hundred five".