21221220022012 has 24 divisors (see below), whose sum is σ = 39091890723200. Its totient is φ = 10052113233456.

The previous prime is 21221220021961. The next prime is 21221220022019. The reversal of 21221220022012 is 21022002212212.

It is a Harshad number since it is a multiple of its sum of digits (19).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221220022019) 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, 23072689 + ... + 23974807.

Almost surely, 2^{21221220022012} is an apocalyptic number.

It is an amenable number.

21221220022012 is a deficient number, since it is larger than the sum of its proper divisors (17870670701188).

21221220022012 is a wasteful number, since it uses less digits than its factorization.

21221220022012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1211665 (or 1211663 counting only the distinct ones).

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

Adding to 21221220022012 its reverse (21022002212212), we get a palindrome (42243222234224).

The spelling of 21221220022012 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred twenty million, twenty-two thousand, twelve".