28558470778 has 4 divisors (see below), whose sum is σ = 42837706170. Its totient is φ = 14279235388.

The previous prime is 28558470749. The next prime is 28558470779. The reversal of 28558470778 is 87707485582.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 87707485582 = 2 ⋅43853742791.

It can be written as a sum of positive squares in only one way, i.e., 20797389369 + 7761081409 = 144213^2 + 88097^2 .

It is not an unprimeable number, because it can be changed into a prime (28558470779) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 7139617693 + ... + 7139617696.

Almost surely, 2^28558470778 is an apocalyptic number.

28558470778 is a deficient number, since it is larger than the sum of its proper divisors (14279235392).

28558470778 is a wasteful number, since it uses less digits than its factorization.

28558470778 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14279235391.

The product of its (nonzero) digits is 35123200, while the sum is 61.

The spelling of 28558470778 in words is "twenty-eight billion, five hundred fifty-eight million, four hundred seventy thousand, seven hundred seventy-eight".