28135705 has 8 divisors (see below), whose sum is σ = 36360072. Its totient is φ = 20777088.

The previous prime is 28135703. The next prime is 28135727. The reversal of 28135705 is 50753182.

It can be written as a sum of positive squares in 4 ways, for example, as 541696 + 27594009 = 736^2 + 5253^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 28135705 - 2¹ = 28135703 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28135703) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 216364 + ... + 216493.

It is an arithmetic number, because the mean of its divisors is an integer number (4545009).

Almost surely, 2^28135705 is an apocalyptic number.

It is an amenable number.

28135705 is a deficient number, since it is larger than the sum of its proper divisors (8224367).

28135705 is a wasteful number, since it uses less digits than its factorization.

28135705 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432875.

The product of its (nonzero) digits is 8400, while the sum is 31.

The square root of 28135705 is about 5304.3100399581. The cubic root of 28135705 is about 304.1486785718.

Adding to 28135705 its reverse (50753182), we get a palindrome (78888887).

The spelling of 28135705 in words is "twenty-eight million, one hundred thirty-five thousand, seven hundred five".