28202117 has 4 divisors (see below), whose sum is σ = 29428320. Its totient is φ = 26975916.

The previous prime is 28202113. The next prime is 28202143. The reversal of 28202117 is 71120282.

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 28202117 - 2² = 28202113 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (23), and also a Moran number because the ratio is a prime number: 1226179 = 28202117 / (2 + 8 + 2 + 0 + 2 + 1 + 1 + 7).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28202092 and 28202101.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28202113) 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, 613067 + ... + 613112.

It is an arithmetic number, because the mean of its divisors is an integer number (7357080).

Almost surely, 2^28202117 is an apocalyptic number.

It is an amenable number.

28202117 is a deficient number, since it is larger than the sum of its proper divisors (1226203).

28202117 is a wasteful number, since it uses less digits than its factorization.

28202117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1226202.

The product of its (nonzero) digits is 448, while the sum is 23.

The square root of 28202117 is about 5310.5665422815. The cubic root of 28202117 is about 304.3877964478.

Adding to 28202117 its reverse (71120282), we get a palindrome (99322399).

The spelling of 28202117 in words is "twenty-eight million, two hundred two thousand, one hundred seventeen".