28138980771 has 32 divisors (see below), whose sum is σ = 48152275200. Its totient is φ = 16050752640.

The previous prime is 28138980739. The next prime is 28138980823. The reversal of 28138980771 is 17708983182.

It is a happy number.

It is not a de Polignac number, because 28138980771 - 2⁵ = 28138980739 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28138980971) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2781541 + ... + 2791638.

It is an arithmetic number, because the mean of its divisors is an integer number (1504758600).

Almost surely, 2^28138980771 is an apocalyptic number.

28138980771 is a deficient number, since it is larger than the sum of its proper divisors (20013294429).

28138980771 is a wasteful number, since it uses less digits than its factorization.

28138980771 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5573216 (or 5573210 counting only the distinct ones).

The product of its (nonzero) digits is 1354752, while the sum is 54.

The spelling of 28138980771 in words is "twenty-eight billion, one hundred thirty-eight million, nine hundred eighty thousand, seven hundred seventy-one".