128606821 has 16 divisors (see below), whose sum is σ = 150774400. Its totient is φ = 109650240.

The previous prime is 128606813. The next prime is 128606827.

128606821 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 128606821 - 2³ = 128606813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128606827) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 71485 + ... + 73261.

It is an arithmetic number, because the mean of its divisors is an integer number (9423400).

Almost surely, 2^128606821 is an apocalyptic number.

It is an amenable number.

128606821 is a deficient number, since it is larger than the sum of its proper divisors (22167579).

128606821 is an equidigital number, since it uses as much as digits as its factorization.

128606821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2009 (or 1995 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 34.

The square root of 128606821 is about 11340.4947422941. The cubic root of 128606821 is about 504.7635673942.

The spelling of 128606821 in words is "one hundred twenty-eight million, six hundred six thousand, eight hundred twenty-one".