218931049 has 4 divisors (see below), whose sum is σ = 231809364. Its totient is φ = 206052736.

The previous prime is 218931047. The next prime is 218931067. The reversal of 218931049 is 940139812.

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 158760000 + 60171049 = 12600^2 + 7757^2 .

It is a cyclic number.

It is not a de Polignac number, because 218931049 - 2¹ = 218931047 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 218930999 and 218931017.

It is not an unprimeable number, because it can be changed into a prime (218931047) 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, 6439132 + ... + 6439165.

It is an arithmetic number, because the mean of its divisors is an integer number (57952341).

Almost surely, 2^218931049 is an apocalyptic number.

It is an amenable number.

218931049 is a deficient number, since it is larger than the sum of its proper divisors (12878315).

218931049 is a wasteful number, since it uses less digits than its factorization.

218931049 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12878314.

The product of its (nonzero) digits is 15552, while the sum is 37.

The square root of 218931049 is about 14796.3187651524. The cubic root of 218931049 is about 602.7017502415.

The spelling of 218931049 in words is "two hundred eighteen million, nine hundred thirty-one thousand, forty-nine".