128217345 has 16 divisors (see below), whose sum is σ = 206226432. Its totient is φ = 68023040.

The previous prime is 128217343. The next prime is 128217359. The reversal of 128217345 is 543712821.

It is not a de Polignac number, because 128217345 - 2¹ = 128217343 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128217343) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19512 + ... + 25241.

It is an arithmetic number, because the mean of its divisors is an integer number (12889152).

Almost surely, 2^128217345 is an apocalyptic number.

128217345 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128217345 is a deficient number, since it is larger than the sum of its proper divisors (78009087).

128217345 is a wasteful number, since it uses less digits than its factorization.

128217345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44952.

The product of its digits is 13440, while the sum is 33.

The square root of 128217345 is about 11323.3098076490. The cubic root of 128217345 is about 504.2535060974.

The spelling of 128217345 in words is "one hundred twenty-eight million, two hundred seventeen thousand, three hundred forty-five".