28638683911 has 4 divisors (see below), whose sum is σ = 28640622024. Its totient is φ = 28636745800.

The previous prime is 28638683893. The next prime is 28638683923. The reversal of 28638683911 is 11938683682.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 11938683682 = 2 ⋅5969341841.

It is a cyclic number.

It is not a de Polignac number, because 28638683911 - 2⁷ = 28638683783 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 (28638683951) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 946720 + ... + 976501.

It is an arithmetic number, because the mean of its divisors is an integer number (7160155506).

Almost surely, 2^28638683911 is an apocalyptic number.

28638683911 is a deficient number, since it is larger than the sum of its proper divisors (1938113).

28638683911 is a wasteful number, since it uses less digits than its factorization.

28638683911 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1938112.

The product of its digits is 2985984, while the sum is 55.

The spelling of 28638683911 in words is "twenty-eight billion, six hundred thirty-eight million, six hundred eighty-three thousand, nine hundred eleven".