128537281 has 4 divisors (see below), whose sum is σ = 129738672. Its totient is φ = 127335892.

The previous prime is 128537273. The next prime is 128537293. The reversal of 128537281 is 182735821.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 128537281 - 2³ = 128537273 is a prime.

It is a super-2 number, since 2×128537281² = 33043665213745922, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 128537281.

It is not an unprimeable number, because it can be changed into a prime (128537231) 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, 600535 + ... + 600748.

It is an arithmetic number, because the mean of its divisors is an integer number (32434668).

Almost surely, 2^128537281 is an apocalyptic number.

It is an amenable number.

128537281 is a deficient number, since it is larger than the sum of its proper divisors (1201391).

128537281 is a wasteful number, since it uses less digits than its factorization.

128537281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1201390.

The product of its digits is 26880, while the sum is 37.

The square root of 128537281 is about 11337.4283239190. The cubic root of 128537281 is about 504.6725727727.

The spelling of 128537281 in words is "one hundred twenty-eight million, five hundred thirty-seven thousand, two hundred eighty-one".