128278017 has 24 divisors (see below), whose sum is σ = 212057664. Its totient is φ = 73198944.

The previous prime is 128277983. The next prime is 128278019. The reversal of 128278017 is 710872821.

It is a happy number.

It is not a de Polignac number, because 128278017 - 2¹⁴ = 128261633 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128278019) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 85758 + ... + 87240.

It is an arithmetic number, because the mean of its divisors is an integer number (8835736).

Almost surely, 2^128278017 is an apocalyptic number.

It is an amenable number.

128278017 is a deficient number, since it is larger than the sum of its proper divisors (83779647).

128278017 is a wasteful number, since it uses less digits than its factorization.

128278017 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2869 (or 2866 counting only the distinct ones).

The product of its (nonzero) digits is 12544, while the sum is 36.

The square root of 128278017 is about 11325.9885661253. The cubic root of 128278017 is about 504.3330305547. Note that the first 3 decimals are identical.

The spelling of 128278017 in words is "one hundred twenty-eight million, two hundred seventy-eight thousand, seventeen".