128557251 has 12 divisors (see below), whose sum is σ = 186382560. Its totient is φ = 85386960.

The previous prime is 128557223. The next prime is 128557259. The reversal of 128557251 is 152755821.

128557251 is a `hidden beast` number, since 1 + 2 + 85 + 572 + 5 + 1 = 666.

It is not a de Polignac number, because 128557251 - 2²⁵ = 95002819 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (128557259) 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 11 ways as a sum of consecutive naturals, for example, 23916 + ... + 28793.

It is an arithmetic number, because the mean of its divisors is an integer number (15531880).

Almost surely, 2^128557251 is an apocalyptic number.

128557251 is a deficient number, since it is larger than the sum of its proper divisors (57825309).

128557251 is a wasteful number, since it uses less digits than its factorization.

128557251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52986 (or 52983 counting only the distinct ones).

The product of its digits is 28000, while the sum is 36.

The square root of 128557251 is about 11338.3090009049. The cubic root of 128557251 is about 504.6987073160.

The spelling of 128557251 in words is "one hundred twenty-eight million, five hundred fifty-seven thousand, two hundred fifty-one".