218871840 has 96 divisors (see below), whose sum is σ = 752141376. Its totient is φ = 53058560.

The previous prime is 218871803. The next prime is 218871857. The reversal of 218871840 is 48178812.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (96).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15447 + ... + 26006.

It is an arithmetic number, because the mean of its divisors is an integer number (7834806).

Almost surely, 2^218871840 is an apocalyptic number.

218871840 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

218871840 is an abundant number, since it is smaller than the sum of its proper divisors (533269536).

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

218871840 is a wasteful number, since it uses less digits than its factorization.

218871840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 41482 (or 41474 counting only the distinct ones).

The product of its (nonzero) digits is 28672, while the sum is 39.

The square root of 218871840 is about 14794.3178281393. The cubic root of 218871840 is about 602.6474126079.

The spelling of 218871840 in words is "two hundred eighteen million, eight hundred seventy-one thousand, eight hundred forty".