21221121211012 has 12 divisors (see below), whose sum is σ = 37138716576220. Its totient is φ = 10610059332096.

The previous prime is 21221121211007. The next prime is 21221121211097. The reversal of 21221121211012 is 21011212112212.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 19335948274756 + 1885172936256 = 4397266^2 + 1373016^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 125223093 + ... + 125392444.

Almost surely, 2^{21221121211012} is an apocalyptic number.

It is an amenable number.

21221121211012 is a deficient number, since it is larger than the sum of its proper divisors (15917595365208).

21221121211012 is a wasteful number, since it uses less digits than its factorization.

21221121211012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 250636710 (or 250636708 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 19.

Adding to 21221121211012 its reverse (21011212112212), we get a palindrome (42232333323224).

The spelling of 21221121211012 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred twenty-one million, two hundred eleven thousand, twelve".