231218290 has 16 divisors (see below), whose sum is σ = 420315480. Its totient is φ = 91571200.

The previous prime is 231218279. The next prime is 231218293. The reversal of 231218290 is 92812132.

It can be written as a sum of positive squares in 4 ways, for example, as 229249881 + 1968409 = 15141^2 + 1403^2 .

It is not an unprimeable number, because it can be changed into a prime (231218293) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 113455 + ... + 115474.

Almost surely, 2^231218290 is an apocalyptic number.

231218290 is a deficient number, since it is larger than the sum of its proper divisors (189097190).

231218290 is a wasteful number, since it uses less digits than its factorization.

231218290 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 229037.

The product of its (nonzero) digits is 1728, while the sum is 28.

The square root of 231218290 is about 15205.8636716235. The cubic root of 231218290 is about 613.7724561534.

It can be divided in two parts, 2312 and 18290, that added together give a palindrome (20602).

The spelling of 231218290 in words is "two hundred thirty-one million, two hundred eighteen thousand, two hundred ninety".