28778057155 has 8 divisors (see below), whose sum is σ = 34555659984. Its totient is φ = 23007784800.

The previous prime is 28778057141. The next prime is 28778057167. The reversal of 28778057155 is 55175087782.

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

It is not a de Polignac number, because 28778057155 - 2⁷ = 28778057027 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28778057096 and 28778057105.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 1823976 + ... + 1839685.

It is an arithmetic number, because the mean of its divisors is an integer number (4319457498).

Almost surely, 2^28778057155 is an apocalyptic number.

28778057155 is a deficient number, since it is larger than the sum of its proper divisors (5777602829).

28778057155 is a wasteful number, since it uses less digits than its factorization.

28778057155 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3665237.

The product of its (nonzero) digits is 5488000, while the sum is 55.

The spelling of 28778057155 in words is "twenty-eight billion, seven hundred seventy-eight million, fifty-seven thousand, one hundred fifty-five".