128581011 has 24 divisors (see below), whose sum is σ = 200578560. Its totient is φ = 78903936.

The previous prime is 128581007. The next prime is 128581067. The reversal of 128581011 is 110185821.

It is not a de Polignac number, because 128581011 - 2² = 128581007 is a prime.

It is not an unprimeable number, because it can be changed into a prime (128581091) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 46510 + ... + 49196.

It is an arithmetic number, because the mean of its divisors is an integer number (8357440).

Almost surely, 2^128581011 is an apocalyptic number.

128581011 is a deficient number, since it is larger than the sum of its proper divisors (71997549).

128581011 is a wasteful number, since it uses less digits than its factorization.

128581011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3115 (or 3112 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 27.

The square root of 128581011 is about 11339.3567277866. The cubic root of 128581011 is about 504.7297982696.

It can be divided in two parts, 1285810 and 11, that added together give a palindrome (1285821).

The spelling of 128581011 in words is "one hundred twenty-eight million, five hundred eighty-one thousand, eleven".