21220214212 has 12 divisors (see below), whose sum is σ = 37137039660. Its totient is φ = 10609631456.

The previous prime is 21220214117. The next prime is 21220214219. The reversal of 21220214212 is 21241202212.

It can be written as a sum of positive squares in 2 ways, for example, as 15169863556 + 6050350656 = 123166^2 + 77784^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 21220214212.

It is not an unprimeable number, because it can be changed into a prime (21220214219) 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, 6787 + ... + 206122.

It is an arithmetic number, because the mean of its divisors is an integer number (3094753305).

Almost surely, 2^21220214212 is an apocalyptic number.

It is an amenable number.

21220214212 is a deficient number, since it is larger than the sum of its proper divisors (15916825448).

21220214212 is a wasteful number, since it uses less digits than its factorization.

21220214212 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 237830 (or 237828 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 19.

Adding to 21220214212 its reverse (21241202212), we get a palindrome (42461416424).

The spelling of 21220214212 in words is "twenty-one billion, two hundred twenty million, two hundred fourteen thousand, two hundred twelve".