28345505 has 8 divisors (see below), whose sum is σ = 34203624. Its totient is φ = 22550400.

The previous prime is 28345483. The next prime is 28345519. The reversal of 28345505 is 50554382.

It can be written as a sum of positive squares in 4 ways, for example, as 529 + 28344976 = 23^2 + 5324^2 .

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

It is not a de Polignac number, because 28345505 - 2¹⁸ = 28083361 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 14756 + ... + 16565.

It is an arithmetic number, because the mean of its divisors is an integer number (4275453).

Almost surely, 2^28345505 is an apocalyptic number.

It is an amenable number.

28345505 is a deficient number, since it is larger than the sum of its proper divisors (5858119).

28345505 is a wasteful number, since it uses less digits than its factorization.

28345505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 31507.

The product of its (nonzero) digits is 24000, while the sum is 32.

The square root of 28345505 is about 5324.0496804594. The cubic root of 28345505 is about 304.9027908430.

Adding to 28345505 its reverse (50554382), we get a palindrome (78899887).

The spelling of 28345505 in words is "twenty-eight million, three hundred forty-five thousand, five hundred five".