128288303882821 has 4 divisors (see below), whose sum is σ = 132712038499500. Its totient is φ = 123864569266144.

The previous prime is 128288303882803. The next prime is 128288303882881.

128288303882821 is nontrivially palindromic in base 10.

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 86657741652196 + 41630562230625 = 9309014^2 + 6452175^2 .

It is a cyclic number.

It is not a de Polignac number, because 128288303882821 - 2⁹ = 128288303882309 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 (128288303882881) 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, 2211867308296 + ... + 2211867308353.

It is an arithmetic number, because the mean of its divisors is an integer number (33178009624875).

Almost surely, 2^{128288303882821} is an apocalyptic number.

It is an amenable number.

128288303882821 is a deficient number, since it is larger than the sum of its proper divisors (4423734616679).

128288303882821 is an equidigital number, since it uses as much as digits as its factorization.

128288303882821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4423734616678.

The product of its (nonzero) digits is 37748736, while the sum is 64.

The spelling of 128288303882821 in words is "one hundred twenty-eight trillion, two hundred eighty-eight billion, three hundred three million, eight hundred eighty-two thousand, eight hundred twenty-one".