218982881 has 8 divisors (see below), whose sum is σ = 237193320. Its totient is φ = 200967552.

The previous prime is 218982859. The next prime is 218982889. The reversal of 218982881 is 188289812.

218982881 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 115777600 + 103205281 = 10760^2 + 10159^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 218982881 - 2⁶ = 218982817 is a prime.

It is a super-2 number, since 2×218982881² = 95907004342120322, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (218982889) 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, 46436 + ... + 50933.

It is an arithmetic number, because the mean of its divisors is an integer number (29649165).

Almost surely, 2^218982881 is an apocalyptic number.

It is an amenable number.

218982881 is a deficient number, since it is larger than the sum of its proper divisors (18210439).

218982881 is a wasteful number, since it uses less digits than its factorization.

218982881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97555.

The product of its digits is 147456, while the sum is 47.

The square root of 218982881 is about 14798.0701782361. The cubic root of 218982881 is about 602.7493097696.

The spelling of 218982881 in words is "two hundred eighteen million, nine hundred eighty-two thousand, eight hundred eighty-one".