218055389 has 4 divisors (see below), whose sum is σ = 218119356. Its totient is φ = 217991424.

The previous prime is 218055377. The next prime is 218055491. The reversal of 218055389 is 983550812.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3667225 + 214388164 = 1915^2 + 14642^2 .

It is a cyclic number.

It is not a de Polignac number, because 218055389 - 2⁴ = 218055373 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218055329) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26564 + ... + 33789.

It is an arithmetic number, because the mean of its divisors is an integer number (54529839).

Almost surely, 2^218055389 is an apocalyptic number.

It is an amenable number.

218055389 is a deficient number, since it is larger than the sum of its proper divisors (63967).

218055389 is an equidigital number, since it uses as much as digits as its factorization.

218055389 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 63966.

The product of its (nonzero) digits is 86400, while the sum is 41.

The square root of 218055389 is about 14766.6986493258. The cubic root of 218055389 is about 601.8971331173.

The spelling of 218055389 in words is "two hundred eighteen million, fifty-five thousand, three hundred eighty-nine".