28720344739 has 2 divisors, whose sum is σ = 28720344740. Its totient is φ = 28720344738.

The previous prime is 28720344713. The next prime is 28720344781. The reversal of 28720344739 is 93744302782.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 28720344739 - 2⁵ = 28720344707 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 28720344692 and 28720344701.

It is not a weakly prime, because it can be changed into another prime (28720344439) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14360172369 + 14360172370.

It is an arithmetic number, because the mean of its divisors is an integer number (14360172370).

Almost surely, 2^28720344739 is an apocalyptic number.

28720344739 is a deficient number, since it is larger than the sum of its proper divisors (1).

28720344739 is an equidigital number, since it uses as much as digits as its factorization.

28720344739 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2032128, while the sum is 49.

The spelling of 28720344739 in words is "twenty-eight billion, seven hundred twenty million, three hundred forty-four thousand, seven hundred thirty-nine".