28133556138 has 12 divisors (see below), whose sum is σ = 60956038338. Its totient is φ = 9377852040.

The previous prime is 28133556119. The next prime is 28133556149. The reversal of 28133556138 is 83165533182.

28133556138 is a `hidden beast` number, since 2 + 81 + 3 + 3 + 5 + 561 + 3 + 8 = 666.

It can be written as a sum of positive squares in only one way, i.e., 21989034369 + 6144521769 = 148287^2 + 78387^2 .

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28133556093 and 28133556102.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 781487653 + ... + 781487688.

Almost surely, 2^28133556138 is an apocalyptic number.

28133556138 is an abundant number, since it is smaller than the sum of its proper divisors (32822482200).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

28133556138 is a wasteful number, since it uses less digits than its factorization.

28133556138 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1562975349 (or 1562975346 counting only the distinct ones).

The product of its digits is 518400, while the sum is 45.

The spelling of 28133556138 in words is "twenty-eight billion, one hundred thirty-three million, five hundred fifty-six thousand, one hundred thirty-eight".