128208817 has 12 divisors (see below), whose sum is σ = 141418368. Its totient is φ = 116144600.

The previous prime is 128208803. The next prime is 128208833. The reversal of 128208817 is 718802821.

It is not a de Polignac number, because 128208817 - 2¹¹ = 128206769 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128208887) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35928 + ... + 39334.

It is an arithmetic number, because the mean of its divisors is an integer number (11784864).

Almost surely, 2^128208817 is an apocalyptic number.

It is an amenable number.

128208817 is a deficient number, since it is larger than the sum of its proper divisors (13209551).

128208817 is a wasteful number, since it uses less digits than its factorization.

128208817 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3740 (or 3729 counting only the distinct ones).

The product of its (nonzero) digits is 14336, while the sum is 37.

The square root of 128208817 is about 11322.9332330452. The cubic root of 128208817 is about 504.2423262027.

The spelling of 128208817 in words is "one hundred twenty-eight million, two hundred eight thousand, eight hundred seventeen".