128282821 has 2 divisors, whose sum is σ = 128282822. Its totient is φ = 128282820.

The previous prime is 128282801. The next prime is 128282831.

128282821 is nontrivially palindromic in base 10.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 106296100 + 21986721 = 10310^2 + 4689^2 .

It is a palprime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128282821 is a prime.

It is a super-3 number, since 3×128282821³ (a number of 25 digits) contains 333 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128282801) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64141410 + 64141411.

It is an arithmetic number, because the mean of its divisors is an integer number (64141411).

Almost surely, 2^128282821 is an apocalyptic number.

It is an amenable number.

128282821 is a deficient number, since it is larger than the sum of its proper divisors (1).

128282821 is an equidigital number, since it uses as much as digits as its factorization.

128282821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8192, while the sum is 34.

The square root of 128282821 is about 11326.2006427575. The cubic root of 128282821 is about 504.3393262180.

The spelling of 128282821 in words is "one hundred twenty-eight million, two hundred eighty-two thousand, eight hundred twenty-one".