28778611389 has 8 divisors (see below), whose sum is σ = 41859798432. Its totient is φ = 17441582640.

The previous prime is 28778611363. The next prime is 28778611399. The reversal of 28778611389 is 98311687782.

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

It is not a de Polignac number, because 28778611389 - 2¹⁷ = 28778480317 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28778611339) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 436039534 + ... + 436039599.

It is an arithmetic number, because the mean of its divisors is an integer number (5232474804).

Almost surely, 2^28778611389 is an apocalyptic number.

It is an amenable number.

28778611389 is a deficient number, since it is larger than the sum of its proper divisors (13081187043).

28778611389 is a wasteful number, since it uses less digits than its factorization.

28778611389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 872079147.

The product of its digits is 8128512, while the sum is 60.

The spelling of 28778611389 in words is "twenty-eight billion, seven hundred seventy-eight million, six hundred eleven thousand, three hundred eighty-nine".