1245728309279 has 4 divisors (see below), whose sum is σ = 1254821216784. Its totient is φ = 1236635401776.

The previous prime is 1245728309261. The next prime is 1245728309299. The reversal of 1245728309279 is 9729038275421.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1245728309279 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1245728309209) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4546453547 + ... + 4546453820.

It is an arithmetic number, because the mean of its divisors is an integer number (313705304196).

Almost surely, 2^{1245728309279} is an apocalyptic number.

1245728309279 is a deficient number, since it is larger than the sum of its proper divisors (9092907505).

1245728309279 is an equidigital number, since it uses as much as digits as its factorization.

1245728309279 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9092907504.

The product of its (nonzero) digits is 15240960, while the sum is 59.

The spelling of 1245728309279 in words is "one trillion, two hundred forty-five billion, seven hundred twenty-eight million, three hundred nine thousand, two hundred seventy-nine".