28878770397 has 4 divisors (see below), whose sum is σ = 38505027200. Its totient is φ = 19252513596.

The previous prime is 28878770363. The next prime is 28878770413. The reversal of 28878770397 is 79307787882.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 28878770397 - 2⁷ = 28878770269 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 (28878770597) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4813128397 + ... + 4813128402.

It is an arithmetic number, because the mean of its divisors is an integer number (9626256800).

Almost surely, 2^28878770397 is an apocalyptic number.

It is an amenable number.

28878770397 is a deficient number, since it is larger than the sum of its proper divisors (9626256803).

28878770397 is an equidigital number, since it uses as much as digits as its factorization.

28878770397 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9626256802.

The product of its (nonzero) digits is 66382848, while the sum is 66.

The spelling of 28878770397 in words is "twenty-eight billion, eight hundred seventy-eight million, seven hundred seventy thousand, three hundred ninety-seven".