28478505 has 16 divisors (see below), whose sum is σ = 49708224. Its totient is φ = 13807680.

The previous prime is 28478503. The next prime is 28478509. The reversal of 28478505 is 50587482.

28478505 = T₂₂₇₀ + T₂₂₇₁ + ... + T₂₂₈₀.

It is not a de Polignac number, because 28478505 - 2¹ = 28478503 is a prime.

It is a super-2 number, since 2×28478505² = 1622050494070050, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28478503) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 86134 + ... + 86463.

It is an arithmetic number, because the mean of its divisors is an integer number (3106764).

Almost surely, 2^28478505 is an apocalyptic number.

It is an amenable number.

28478505 is a deficient number, since it is larger than the sum of its proper divisors (21229719).

28478505 is a wasteful number, since it uses less digits than its factorization.

28478505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172616.

The product of its (nonzero) digits is 89600, while the sum is 39.

The square root of 28478505 is about 5336.5255550779. The cubic root of 28478505 is about 305.3789252563.

The spelling of 28478505 in words is "twenty-eight million, four hundred seventy-eight thousand, five hundred five".