218140321 has 8 divisors (see below), whose sum is σ = 250977600. Its totient is φ = 185721648.

The previous prime is 218140309. The next prime is 218140327. The reversal of 218140321 is 123041812.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 218140321 - 2⁵ = 218140289 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 218140292 and 218140301.

It is not an unprimeable number, because it can be changed into a prime (218140327) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 103531 + ... + 105616.

It is an arithmetic number, because the mean of its divisors is an integer number (31372200).

Almost surely, 2^218140321 is an apocalyptic number.

It is an amenable number.

218140321 is a deficient number, since it is larger than the sum of its proper divisors (32837279).

218140321 is a wasteful number, since it uses less digits than its factorization.

218140321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209303.

The product of its (nonzero) digits is 384, while the sum is 22.

The square root of 218140321 is about 14769.5741644775. The cubic root of 218140321 is about 601.9752687566.

The spelling of 218140321 in words is "two hundred eighteen million, one hundred forty thousand, three hundred twenty-one".