128101821 has 16 divisors (see below), whose sum is σ = 174919680. Its totient is φ = 83366640.

The previous prime is 128101801. The next prime is 128101847.

128101821 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 128101821 - 2⁷ = 128101693 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 128101791 and 128101800.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128101801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19020 + ... + 24858.

It is an arithmetic number, because the mean of its divisors is an integer number (10932480).

Almost surely, 2^128101821 is an apocalyptic number.

It is an amenable number.

128101821 is a deficient number, since it is larger than the sum of its proper divisors (46817859).

128101821 is a wasteful number, since it uses less digits than its factorization.

128101821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6016.

The product of its (nonzero) digits is 256, while the sum is 24.

The square root of 128101821 is about 11318.2074994232. The cubic root of 128101821 is about 504.1020162287.

The spelling of 128101821 in words is "one hundred twenty-eight million, one hundred one thousand, eight hundred twenty-one".