28383661821 has 4 divisors (see below), whose sum is σ = 37844882432. Its totient is φ = 18922441212.

The previous prime is 28383661763. The next prime is 28383661843. The reversal of 28383661821 is 12816638382.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 28383661821 - 2¹⁰ = 28383660797 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 (28383661021) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4730610301 + ... + 4730610306.

It is an arithmetic number, because the mean of its divisors is an integer number (9461220608).

Almost surely, 2^28383661821 is an apocalyptic number.

It is an amenable number.

28383661821 is a deficient number, since it is larger than the sum of its proper divisors (9461220611).

28383661821 is an equidigital number, since it uses as much as digits as its factorization.

28383661821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9461220610.

The product of its digits is 663552, while the sum is 48.

The spelling of 28383661821 in words is "twenty-eight billion, three hundred eighty-three million, six hundred sixty-one thousand, eight hundred twenty-one".