21221010021012 has 24 divisors (see below), whose sum is σ = 49722868675200. Its totient is φ = 7044073060416.

The previous prime is 21221010020993. The next prime is 21221010021019. The reversal of 21221010021012 is 21012001012212.

It is a junction number, because it is equal to n+sod(n) for n = 21221010020982 and 21221010021000.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221010021019) 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, 3699615337 + ... + 3699621072.

It is an arithmetic number, because the mean of its divisors is an integer number (2071786194800).

Almost surely, 2^{21221010021012} is an apocalyptic number.

It is an amenable number.

21221010021012 is an abundant number, since it is smaller than the sum of its proper divisors (28501858654188).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21221010021012 is a wasteful number, since it uses less digits than its factorization.

21221010021012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7399236655 (or 7399236653 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 21221010021012 its reverse (21012001012212), we get a palindrome (42233011033224).

The spelling of 21221010021012 in words is "twenty-one trillion, two hundred twenty-one billion, ten million, twenty-one thousand, twelve".