28109518642 has 4 divisors (see below), whose sum is σ = 42164277966. Its totient is φ = 14054759320.

The previous prime is 28109518583. The next prime is 28109518673. The reversal of 28109518642 is 24681590182.

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

It can be written as a sum of positive squares in only one way, i.e., 27835251921 + 274266721 = 166839^2 + 16561^2 .

It is a junction number, because it is equal to n+sod(n) for n = 28109518592 and 28109518601.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7027379659 + ... + 7027379662.

Almost surely, 2^28109518642 is an apocalyptic number.

28109518642 is a deficient number, since it is larger than the sum of its proper divisors (14054759324).

28109518642 is a wasteful number, since it uses less digits than its factorization.

28109518642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14054759323.

The product of its (nonzero) digits is 276480, while the sum is 46.

The spelling of 28109518642 in words is "twenty-eight billion, one hundred nine million, five hundred eighteen thousand, six hundred forty-two".