28031317 has 8 divisors (see below), whose sum is σ = 30312576. Its totient is φ = 25820352.

The previous prime is 28031309. The next prime is 28031321. The reversal of 28031317 is 71313082.

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 28031317 - 2³ = 28031309 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28031291 and 28031300.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28031417) 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, 16743 + ... + 18340.

It is an arithmetic number, because the mean of its divisors is an integer number (3789072).

Almost surely, 2^28031317 is an apocalyptic number.

It is an amenable number.

28031317 is a deficient number, since it is larger than the sum of its proper divisors (2281259).

28031317 is a wasteful number, since it uses less digits than its factorization.

28031317 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35147.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 28031317 is about 5294.4609735081. The cubic root of 28031317 is about 303.7720655503.

Adding to 28031317 its reverse (71313082), we get a palindrome (99344399).

The spelling of 28031317 in words is "twenty-eight million, thirty-one thousand, three hundred seventeen".