221312021212 has 24 divisors (see below), whose sum is σ = 387869050800. Its totient is φ = 110492409216.

The previous prime is 221312021171. The next prime is 221312021243. The reversal of 221312021212 is 212120213122.

It is a self number, because there is not a number n which added to its sum of digits gives 221312021212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 8449128 + ... + 8475280.

It is an arithmetic number, because the mean of its divisors is an integer number (16161210450).

Almost surely, 2^221312021212 is an apocalyptic number.

It is an amenable number.

221312021212 is a deficient number, since it is larger than the sum of its proper divisors (166557029588).

221312021212 is a wasteful number, since it uses less digits than its factorization.

221312021212 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29205 (or 29203 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 19.

Adding to 221312021212 its reverse (212120213122), we get a palindrome (433432234334).

The spelling of 221312021212 in words is "two hundred twenty-one billion, three hundred twelve million, twenty-one thousand, two hundred twelve".