28378747447 has 4 divisors (see below), whose sum is σ = 28386880056. Its totient is φ = 28370614840.

The previous prime is 28378747417. The next prime is 28378747483. The reversal of 28378747447 is 74474787382.

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-28378747447 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 (28378747417) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4061068 + ... + 4068049.

It is an arithmetic number, because the mean of its divisors is an integer number (7096720014).

Almost surely, 2^28378747447 is an apocalyptic number.

28378747447 is a deficient number, since it is larger than the sum of its proper divisors (8132609).

28378747447 is an equidigital number, since it uses as much as digits as its factorization.

28378747447 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8132608.

The product of its digits is 59006976, while the sum is 61.

The spelling of 28378747447 in words is "twenty-eight billion, three hundred seventy-eight million, seven hundred forty-seven thousand, four hundred forty-seven".