28209101 has 4 divisors (see below), whose sum is σ = 29119104. Its totient is φ = 27299100.

The previous prime is 28209061. The next prime is 28209119. The reversal of 28209101 is 10190282.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 28209101 - 2⁶ = 28209037 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28209121) 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, 454955 + ... + 455016.

It is an arithmetic number, because the mean of its divisors is an integer number (7279776).

Almost surely, 2^28209101 is an apocalyptic number.

It is an amenable number.

28209101 is a deficient number, since it is larger than the sum of its proper divisors (910003).

28209101 is an equidigital number, since it uses as much as digits as its factorization.

28209101 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 910002.

The product of its (nonzero) digits is 288, while the sum is 23.

The square root of 28209101 is about 5311.2240585387. The cubic root of 28209101 is about 304.4129206718.

Adding to 28209101 its reverse (10190282), we get a palindrome (38399383).

The spelling of 28209101 in words is "twenty-eight million, two hundred nine thousand, one hundred one".