128564550 has 48 divisors (see below), whose sum is σ = 354270480. Its totient is φ = 34283520.

The previous prime is 128564537. The next prime is 128564551. The reversal of 128564550 is 55465821.

128564550 is a `hidden beast` number, since 1 + 2 + 8 + 5 + 645 + 5 + 0 = 666.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128564551) 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, 46267 + ... + 48966.

It is an arithmetic number, because the mean of its divisors is an integer number (7380635).

Almost surely, 2^128564550 is an apocalyptic number.

128564550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

128564550 is an abundant number, since it is smaller than the sum of its proper divisors (225705930).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

128564550 is a wasteful number, since it uses less digits than its factorization.

128564550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 95254 (or 95243 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 36.

The square root of 128564550 is about 11338.6308697303. The cubic root of 128564550 is about 504.7082587703.

The spelling of 128564550 in words is "one hundred twenty-eight million, five hundred sixty-four thousand, five hundred fifty".