128000001 has 4 divisors (see below), whose sum is σ = 170666672. Its totient is φ = 85333332.

The previous prime is 127999981. The next prime is 128000003. The reversal of 128000001 is 100000821.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 128000001 - 2⁷ = 127999873 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128000003) 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, 21333331 + ... + 21333336.

It is an arithmetic number, because the mean of its divisors is an integer number (42666668).

Almost surely, 2^128000001 is an apocalyptic number.

It is an amenable number.

128000001 is a deficient number, since it is larger than the sum of its proper divisors (42666671).

128000001 is an equidigital number, since it uses as much as digits as its factorization.

128000001 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42666670.

The product of its (nonzero) digits is 16, while the sum is 12.

The square root of 128000001 is about 11313.7085431789. The cubic root of 128000001 is about 503.9684212704.

Adding to 128000001 its reverse (100000821), we get a palindrome (228000822).

The spelling of 128000001 in words is "one hundred twenty-eight million, one", and thus it is an aban number.