28683780821 has 8 divisors (see below), whose sum is σ = 28850308320. Its totient is φ = 28517732208.

The previous prime is 28683780817. The next prime is 28683780841. The reversal of 28683780821 is 12808738682.

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 28683780821 - 2² = 28683780817 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28683780841) 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, 770 + ... + 239516.

It is an arithmetic number, because the mean of its divisors is an integer number (3606288540).

Almost surely, 2^28683780821 is an apocalyptic number.

It is an amenable number.

28683780821 is a deficient number, since it is larger than the sum of its proper divisors (166527499).

28683780821 is a wasteful number, since it uses less digits than its factorization.

28683780821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 239443.

The product of its (nonzero) digits is 2064384, while the sum is 53.

The spelling of 28683780821 in words is "twenty-eight billion, six hundred eighty-three million, seven hundred eighty thousand, eight hundred twenty-one".