128264565 has 32 divisors (see below), whose sum is σ = 241105536. Its totient is φ = 57404160.

The previous prime is 128264509. The next prime is 128264569. The reversal of 128264565 is 565462821.

It is not a de Polignac number, because 128264565 - 2⁶ = 128264501 is a prime.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128264569) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 27754 + ... + 32043.

It is an arithmetic number, because the mean of its divisors is an integer number (7534548).

Almost surely, 2^128264565 is an apocalyptic number.

128264565 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128264565 is a deficient number, since it is larger than the sum of its proper divisors (112840971).

128264565 is a wasteful number, since it uses less digits than its factorization.

128264565 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59829.

The product of its digits is 115200, while the sum is 39.

The square root of 128264565 is about 11325.3946951089. The cubic root of 128264565 is about 504.3154008125.

It can be divided in two parts, 12826 and 4565, that added together give a triangular number (17391 = T₁₈₆).

The spelling of 128264565 in words is "one hundred twenty-eight million, two hundred sixty-four thousand, five hundred sixty-five".