28785653 has 4 divisors (see below), whose sum is σ = 30999948. Its totient is φ = 26571360.

The previous prime is 28785629. The next prime is 28785683. The reversal of 28785653 is 35658782.

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 5726449 + 23059204 = 2393^2 + 4802^2 .

It is a cyclic number.

It is not a de Polignac number, because 28785653 - 2¹⁰ = 28784629 is a prime.

It is a super-2 number, since 2×28785653² = 1657227637272818, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28785683) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1107128 + ... + 1107153.

It is an arithmetic number, because the mean of its divisors is an integer number (7749987).

Almost surely, 2^28785653 is an apocalyptic number.

It is an amenable number.

28785653 is a deficient number, since it is larger than the sum of its proper divisors (2214295).

28785653 is a wasteful number, since it uses less digits than its factorization.

28785653 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2214294.

The product of its digits is 403200, while the sum is 44.

The square root of 28785653 is about 5365.2262766821. The cubic root of 28785653 is about 306.4728652372.

The spelling of 28785653 in words is "twenty-eight million, seven hundred eighty-five thousand, six hundred fifty-three".