28581545 has 4 divisors (see below), whose sum is σ = 34297860. Its totient is φ = 22865232.

The previous prime is 28581533. The next prime is 28581569. The reversal of 28581545 is 54518582.

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

It can be written as a sum of positive squares in 2 ways, for example, as 8340544 + 20241001 = 2888^2 + 4499^2 .

It is a cyclic number.

It is not a de Polignac number, because 28581545 - 2⁶ = 28581481 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 28581499 and 28581508.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2858150 + ... + 2858159.

It is an arithmetic number, because the mean of its divisors is an integer number (8574465).

Almost surely, 2^28581545 is an apocalyptic number.

It is an amenable number.

28581545 is a deficient number, since it is larger than the sum of its proper divisors (5716315).

28581545 is an equidigital number, since it uses as much as digits as its factorization.

28581545 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5716314.

The product of its digits is 64000, while the sum is 38.

The square root of 28581545 is about 5346.1710597399. The cubic root of 28581545 is about 305.7467859816.

The spelling of 28581545 in words is "twenty-eight million, five hundred eighty-one thousand, five hundred forty-five".