128265587 has 4 divisors (see below), whose sum is σ = 130439640. Its totient is φ = 126091536.

The previous prime is 128265581. The next prime is 128265601. The reversal of 128265587 is 785562821.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 128265587 - 2²⁰ = 127217011 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128265581) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1086938 + ... + 1087055.

It is an arithmetic number, because the mean of its divisors is an integer number (32609910).

Almost surely, 2^128265587 is an apocalyptic number.

128265587 is a deficient number, since it is larger than the sum of its proper divisors (2174053).

128265587 is an equidigital number, since it uses as much as digits as its factorization.

128265587 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2174052.

The product of its digits is 268800, while the sum is 44.

The square root of 128265587 is about 11325.4398148593. The cubic root of 128265587 is about 504.3167402549.

The spelling of 128265587 in words is "one hundred twenty-eight million, two hundred sixty-five thousand, five hundred eighty-seven".