128331001 has 2 divisors, whose sum is σ = 128331002. Its totient is φ = 128331000.

The previous prime is 128330999. The next prime is 128331019. The reversal of 128331001 is 100133821.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 122323600 + 6007401 = 11060^2 + 2451^2 .

It is a cyclic number.

It is not a de Polignac number, because 128331001 - 2¹ = 128330999 is a prime.

Together with 128330999, it forms a pair of twin primes.

It is a self number, because there is not a number n which added to its sum of digits gives 128331001.

It is not a weakly prime, because it can be changed into another prime (128331901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64165500 + 64165501.

It is an arithmetic number, because the mean of its divisors is an integer number (64165501).

Almost surely, 2^128331001 is an apocalyptic number.

It is an amenable number.

128331001 is a deficient number, since it is larger than the sum of its proper divisors (1).

128331001 is an equidigital number, since it uses as much as digits as its factorization.

128331001 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 128331001 is about 11328.3273699165. The cubic root of 128331001 is about 504.4024576312.

Adding to 128331001 its reverse (100133821), we get a palindrome (228464822).

The spelling of 128331001 in words is "one hundred twenty-eight million, three hundred thirty-one thousand, one".