218009153 has 4 divisors (see below), whose sum is σ = 225526740. Its totient is φ = 210491568.

The previous prime is 218009147. The next prime is 218009213. The reversal of 218009153 is 351900812.

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 81306289 + 136702864 = 9017^2 + 11692^2 .

It is a cyclic number.

It is not a de Polignac number, because 218009153 - 2¹² = 218005057 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (29), and also a Moran number because the ratio is a prime number: 7517557 = 218009153 / (2 + 1 + 8 + 0 + 0 + 9 + 1 + 5 + 3).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (218009653) 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, 3758750 + ... + 3758807.

It is an arithmetic number, because the mean of its divisors is an integer number (56381685).

Almost surely, 2^218009153 is an apocalyptic number.

It is an amenable number.

218009153 is a deficient number, since it is larger than the sum of its proper divisors (7517587).

218009153 is an equidigital number, since it uses as much as digits as its factorization.

218009153 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7517586.

The product of its (nonzero) digits is 2160, while the sum is 29.

The square root of 218009153 is about 14765.1330166714. The cubic root of 218009153 is about 601.8545884483.

Adding to 218009153 its reverse (351900812), we get a palindrome (569909965).

The spelling of 218009153 in words is "two hundred eighteen million, nine thousand, one hundred fifty-three".