28785605 has 4 divisors (see below), whose sum is σ = 34542732. Its totient is φ = 23028480.

The previous prime is 28785599. The next prime is 28785629. The reversal of 28785605 is 50658782.

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 5764801 + 23020804 = 2401^2 + 4798^2 .

It is not a de Polignac number, because 28785605 - 2⁶ = 28785541 is a prime.

It is a super-2 number, since 2×28785605² = 1657222110432050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2878556 + ... + 2878565.

It is an arithmetic number, because the mean of its divisors is an integer number (8635683).

Almost surely, 2^28785605 is an apocalyptic number.

It is an amenable number.

28785605 is a deficient number, since it is larger than the sum of its proper divisors (5757127).

28785605 is an equidigital number, since it uses as much as digits as its factorization.

28785605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5757126.

The product of its (nonzero) digits is 134400, while the sum is 41.

The square root of 28785605 is about 5365.2218034299. The cubic root of 28785605 is about 306.4726948896.

The spelling of 28785605 in words is "twenty-eight million, seven hundred eighty-five thousand, six hundred five".