28481578 has 4 divisors (see below), whose sum is σ = 42722370. Its totient is φ = 14240788.

The previous prime is 28481573. The next prime is 28481603. The reversal of 28481578 is 87518482.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 15499969 + 12981609 = 3937^2 + 3603^2 .

It is a super-2 number, since 2×28481578² = 1622400570740168, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28481573) 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 as a sum of consecutive naturals, namely, 7120393 + ... + 7120396.

Almost surely, 2^28481578 is an apocalyptic number.

28481578 is a deficient number, since it is larger than the sum of its proper divisors (14240792).

28481578 is a wasteful number, since it uses less digits than its factorization.

28481578 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 14240791.

The product of its digits is 143360, while the sum is 43.

The square root of 28481578 is about 5336.8134687283. The cubic root of 28481578 is about 305.3899089285.

The spelling of 28481578 in words is "twenty-eight million, four hundred eighty-one thousand, five hundred seventy-eight".