21201221222212 has 6 divisors (see below), whose sum is σ = 37102137138878. Its totient is φ = 10600610611104.

The previous prime is 21201221222011. The next prime is 21201221222249. The reversal of 21201221222212 is 21222212210212.

It can be written as a sum of positive squares in only one way, i.e., 20491610418756 + 709610803456 = 4526766^2 + 842384^2 .

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2650152652773 + ... + 2650152652780.

Almost surely, 2^{21201221222212} is an apocalyptic number.

It is an amenable number.

21201221222212 is a deficient number, since it is larger than the sum of its proper divisors (15900915916666).

21201221222212 is a wasteful number, since it uses less digits than its factorization.

21201221222212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5300305305557 (or 5300305305555 counting only the distinct ones).

The product of its (nonzero) digits is 512, while the sum is 22.

Adding to 21201221222212 its reverse (21222212210212), we get a palindrome (42423433432424).

The spelling of 21201221222212 in words is "twenty-one trillion, two hundred one billion, two hundred twenty-one million, two hundred twenty-two thousand, two hundred twelve".