128945505 has 16 divisors (see below), whose sum is σ = 222183360. Its totient is φ = 63480768.

The previous prime is 128945501. The next prime is 128945569. The reversal of 128945505 is 505549821.

It is not a de Polignac number, because 128945505 - 2² = 128945501 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (128945501) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 330435 + ... + 330824.

It is an arithmetic number, because the mean of its divisors is an integer number (13886460).

Almost surely, 2^128945505 is an apocalyptic number.

128945505 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128945505 is a deficient number, since it is larger than the sum of its proper divisors (93237855).

128945505 is a wasteful number, since it uses less digits than its factorization.

128945505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 661280.

The product of its (nonzero) digits is 72000, while the sum is 39.

The square root of 128945505 is about 11355.4174295796. The cubic root of 128945505 is about 505.2062745864.

The spelling of 128945505 in words is "one hundred twenty-eight million, nine hundred forty-five thousand, five hundred five".