28117643618 has 8 divisors (see below), whose sum is σ = 43316370012. Its totient is φ = 13678853616.

The previous prime is 28117643537. The next prime is 28117643621. The reversal of 28117643618 is 81634671182.

It can be written as a sum of positive squares in 2 ways, for example, as 24107841289 + 4009802329 = 155267^2 + 63323^2 .

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

It is a super-2 number, since 2×28117643618² (a number of 22 digits) contains 22 as substring.

It is a Curzon number.

It is an unprimeable number.

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, 189984005 + ... + 189984152.

Almost surely, 2^28117643618 is an apocalyptic number.

28117643618 is a deficient number, since it is larger than the sum of its proper divisors (15198726394).

28117643618 is a wasteful number, since it uses less digits than its factorization.

28117643618 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 379968196.

The product of its digits is 387072, while the sum is 47.

The spelling of 28117643618 in words is "twenty-eight billion, one hundred seventeen million, six hundred forty-three thousand, six hundred eighteen".