28285751021 has 8 divisors (see below), whose sum is σ = 30930832800. Its totient is φ = 25652944240.

The previous prime is 28285751017. The next prime is 28285751029. The reversal of 28285751021 is 12015758282.

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

It is not a de Polignac number, because 28285751021 - 2² = 28285751017 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 28285751021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28285751029) 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, 3063926 + ... + 3073143.

It is an arithmetic number, because the mean of its divisors is an integer number (3866354100).

Almost surely, 2^28285751021 is an apocalyptic number.

It is an amenable number.

28285751021 is a deficient number, since it is larger than the sum of its proper divisors (2645081779).

28285751021 is a wasteful number, since it uses less digits than its factorization.

28285751021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6137499.

The product of its (nonzero) digits is 89600, while the sum is 41.

The spelling of 28285751021 in words is "twenty-eight billion, two hundred eighty-five million, seven hundred fifty-one thousand, twenty-one".