21212200012 has 24 divisors (see below), whose sum is σ = 38050855920. Its totient is φ = 10340855040.

The previous prime is 21212199929. The next prime is 21212200013. The reversal of 21212200012 is 21000221212.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 21212199965 and 21212200001.

It is not an unprimeable number, because it can be changed into a prime (21212200013) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 223683 + ... + 304069.

It is an arithmetic number, because the mean of its divisors is an integer number (1585452330).

Almost surely, 2^21212200012 is an apocalyptic number.

It is an amenable number.

21212200012 is a deficient number, since it is larger than the sum of its proper divisors (16838655908).

21212200012 is a wasteful number, since it uses less digits than its factorization.

21212200012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 82041 (or 82039 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 21212200012 its reverse (21000221212), we get a palindrome (42212421224).

The spelling of 21212200012 in words is "twenty-one billion, two hundred twelve million, two hundred thousand, twelve".