218128550 has 96 divisors (see below), whose sum is σ = 455328000. Its totient is φ = 77362560.

The previous prime is 218128541. The next prime is 218128567. The reversal of 218128550 is 55821812.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1463876 + ... + 1464024.

It is an arithmetic number, because the mean of its divisors is an integer number (4743000).

Almost surely, 2^218128550 is an apocalyptic number.

218128550 is an abundant number, since it is smaller than the sum of its proper divisors (237199450).

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

218128550 is a wasteful number, since it uses less digits than its factorization.

218128550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 270 (or 265 counting only the distinct ones).

The product of its (nonzero) digits is 6400, while the sum is 32.

The square root of 218128550 is about 14769.1756709709. The cubic root of 218128550 is about 601.9644408969.

The spelling of 218128550 in words is "two hundred eighteen million, one hundred twenty-eight thousand, five hundred fifty".