128287427 has 4 divisors (see below), whose sum is σ = 129533040. Its totient is φ = 127041816.

The previous prime is 128287421. The next prime is 128287429. The reversal of 128287427 is 724782821.

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 128287427 - 2²⁰ = 127238851 is a prime.

It is a super-3 number, since 3×128287427³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128287421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 622652 + ... + 622857.

It is an arithmetic number, because the mean of its divisors is an integer number (32383260).

Almost surely, 2^128287427 is an apocalyptic number.

128287427 is a deficient number, since it is larger than the sum of its proper divisors (1245613).

128287427 is a wasteful number, since it uses less digits than its factorization.

128287427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1245612.

The product of its digits is 100352, while the sum is 41.

The square root of 128287427 is about 11326.4039747839. The cubic root of 128287427 is about 504.3453622539.

The spelling of 128287427 in words is "one hundred twenty-eight million, two hundred eighty-seven thousand, four hundred twenty-seven".