28430285849821 has 4 divisors (see below), whose sum is σ = 28435476705372. Its totient is φ = 28425094994272.

The previous prime is 28430285849803. The next prime is 28430285849837. The reversal of 28430285849821 is 12894858203482.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 17029331008921 + 11400954840900 = 4126661^2 + 3376530^2 .

It is a cyclic number.

It is not a de Polignac number, because 28430285849821 - 2²⁷ = 28430151632093 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 (28430285840821) 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, 2595419560 + ... + 2595430513.

It is an arithmetic number, because the mean of its divisors is an integer number (7108869176343).

Almost surely, 2^{28430285849821} is an apocalyptic number.

It is an amenable number.

28430285849821 is a deficient number, since it is larger than the sum of its proper divisors (5190855551).

28430285849821 is an equidigital number, since it uses as much as digits as its factorization.

28430285849821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5190855550.

The product of its (nonzero) digits is 70778880, while the sum is 64.

The spelling of 28430285849821 in words is "twenty-eight trillion, four hundred thirty billion, two hundred eighty-five million, eight hundred forty-nine thousand, eight hundred twenty-one".