21221231012 has 12 divisors (see below), whose sum is σ = 37169427456. Its totient is φ = 10601394600.

The previous prime is 21221231011. The next prime is 21221231021. The reversal of 21221231012 is 21013212212.

It is not an unprimeable number, because it can be changed into a prime (21221231011) 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, 2300048 + ... + 2309255.

It is an arithmetic number, because the mean of its divisors is an integer number (3097452288).

Almost surely, 2^21221231012 is an apocalyptic number.

It is an amenable number.

21221231012 is a deficient number, since it is larger than the sum of its proper divisors (15948196444).

21221231012 is a wasteful number, since it uses less digits than its factorization.

21221231012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4610458 (or 4610456 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 21221231012 its reverse (21013212212), we get a palindrome (42234443224).

The spelling of 21221231012 in words is "twenty-one billion, two hundred twenty-one million, two hundred thirty-one thousand, twelve".