28017819649 has 8 divisors (see below), whose sum is σ = 28143839880. Its totient is φ = 27891849216.

The previous prime is 28017819647. The next prime is 28017819703. The reversal of 28017819649 is 94691871082.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 4649194225 + 23368625424 = 68185^2 + 152868^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 28017819649 - 2¹ = 28017819647 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28017819649.

It is not an unprimeable number, because it can be changed into a prime (28017819647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1549549 + ... + 1567525.

It is an arithmetic number, because the mean of its divisors is an integer number (3517979985).

Almost surely, 2^28017819649 is an apocalyptic number.

It is an amenable number.

28017819649 is a deficient number, since it is larger than the sum of its proper divisors (126020231).

28017819649 is a wasteful number, since it uses less digits than its factorization.

28017819649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24899.

The product of its (nonzero) digits is 1741824, while the sum is 55.

The spelling of 28017819649 in words is "twenty-eight billion, seventeen million, eight hundred nineteen thousand, six hundred forty-nine".