21031212230 has 32 divisors (see below), whose sum is σ = 43909952256. Its totient is φ = 7103077344.

The previous prime is 21031212229. The next prime is 21031212361. The reversal of 21031212230 is 3221213012.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21031212199 and 21031212208.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2237444 + ... + 2246823.

It is an arithmetic number, because the mean of its divisors is an integer number (1372186008).

Almost surely, 2^21031212230 is an apocalyptic number.

21031212230 is an abundant number, since it is smaller than the sum of its proper divisors (22878740026).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21031212230 is a wasteful number, since it uses less digits than its factorization.

21031212230 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4484348.

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21031212230 its reverse (3221213012), we get a palindrome (24252425242).

The spelling of 21031212230 in words is "twenty-one billion, thirty-one million, two hundred twelve thousand, two hundred thirty".