28820517 has 8 divisors (see below), whose sum is σ = 41920800. Its totient is φ = 17466960.

The previous prime is 28820513. The next prime is 28820527. The reversal of 28820517 is 71502882.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 28820517 - 2² = 28820513 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33), and also a Moran number because the ratio is a prime number: 873349 = 28820517 / (2 + 8 + 8 + 2 + 0 + 5 + 1 + 7).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28820513) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 436642 + ... + 436707.

It is an arithmetic number, because the mean of its divisors is an integer number (5240100).

Almost surely, 2^28820517 is an apocalyptic number.

It is an amenable number.

28820517 is a deficient number, since it is larger than the sum of its proper divisors (13100283).

28820517 is a wasteful number, since it uses less digits than its factorization.

28820517 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 873363.

The product of its (nonzero) digits is 8960, while the sum is 33.

The square root of 28820517 is about 5368.4743642864. The cubic root of 28820517 is about 306.5965444323.

The spelling of 28820517 in words is "twenty-eight million, eight hundred twenty thousand, five hundred seventeen".