21221000222210 has 16 divisors (see below), whose sum is σ = 38198016767736. Its totient is φ = 8488352007168.

The previous prime is 21221000222173. The next prime is 21221000222221. The reversal of 21221000222210 is 1222200012212.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 20476339956241 + 744660265969 = 4525079^2 + 862937^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4128479 + ... + 7712738.

Almost surely, 2^{21221000222210} is an apocalyptic number.

21221000222210 is a deficient number, since it is larger than the sum of its proper divisors (16977016545526).

21221000222210 is a wasteful number, since it uses less digits than its factorization.

21221000222210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12020437.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 21221000222210 its reverse (1222200012212), we get a palindrome (22443200234422).

It can be divided in two parts, 212210002 and 22210, that added together give a palindrome (212232212).

The spelling of 21221000222210 in words is "twenty-one trillion, two hundred twenty-one billion, two hundred twenty-two thousand, two hundred ten".