28285821817 has 8 divisors (see below), whose sum is σ = 31363117632. Its totient is φ = 25292835600.

The previous prime is 28285821799. The next prime is 28285821833. The reversal of 28285821817 is 71812858282.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28285821817 is a prime.

It is not an unprimeable number, because it can be changed into a prime (28285821887) 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, 21076693 + ... + 21078034.

It is an arithmetic number, because the mean of its divisors is an integer number (3920389704).

Almost surely, 2^28285821817 is an apocalyptic number.

It is an amenable number.

28285821817 is a deficient number, since it is larger than the sum of its proper divisors (3077295815).

28285821817 is a wasteful number, since it uses less digits than its factorization.

28285821817 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42154799.

The product of its digits is 1146880, while the sum is 52.

The spelling of 28285821817 in words is "twenty-eight billion, two hundred eighty-five million, eight hundred twenty-one thousand, eight hundred seventeen".