28817645 has 4 divisors (see below), whose sum is σ = 34581180. Its totient is φ = 23054112.

The previous prime is 28817641. The next prime is 28817647. The reversal of 28817645 is 54671882.

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 4502884 + 24314761 = 2122^2 + 4931^2 .

It is a cyclic number.

It is not a de Polignac number, because 28817645 - 2² = 28817641 is a prime.

It is a super-3 number, since 3×28817645³ (a number of 23 digits) contains 333 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28817641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2881760 + ... + 2881769.

It is an arithmetic number, because the mean of its divisors is an integer number (8645295).

Almost surely, 2^28817645 is an apocalyptic number.

It is an amenable number.

28817645 is a deficient number, since it is larger than the sum of its proper divisors (5763535).

28817645 is an equidigital number, since it uses as much as digits as its factorization.

28817645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5763534.

The product of its digits is 107520, while the sum is 41.

The square root of 28817645 is about 5368.2068700824. The cubic root of 28817645 is about 306.5863598530.

The spelling of 28817645 in words is "twenty-eight million, eight hundred seventeen thousand, six hundred forty-five".