128256120281 has 8 divisors (see below), whose sum is σ = 130997504640. Its totient is φ = 125515258128.

The previous prime is 128256120229. The next prime is 128256120287. The reversal of 128256120281 is 182021652821.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-128256120281 is a prime.

It is a super-2 number, since 2×128256120281² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128256120287) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 387650 + ... + 637796.

It is an arithmetic number, because the mean of its divisors is an integer number (16374688080).

Almost surely, 2^128256120281 is an apocalyptic number.

It is an amenable number.

128256120281 is a deficient number, since it is larger than the sum of its proper divisors (2741384359).

128256120281 is a wasteful number, since it uses less digits than its factorization.

128256120281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 261103.

The product of its (nonzero) digits is 30720, while the sum is 38.

The spelling of 128256120281 in words is "one hundred twenty-eight billion, two hundred fifty-six million, one hundred twenty thousand, two hundred eighty-one".