21221065106 has 16 divisors (see below), whose sum is σ = 33018067104. Its totient is φ = 10221803424.

The previous prime is 21221065079. The next prime is 21221065163. The reversal of 21221065106 is 60156012212.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1683836 + ... + 1696391.

It is an arithmetic number, because the mean of its divisors is an integer number (2063629194).

Almost surely, 2^21221065106 is an apocalyptic number.

21221065106 is a deficient number, since it is larger than the sum of its proper divisors (11797001998).

21221065106 is a wasteful number, since it uses less digits than its factorization.

21221065106 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3380345.

The product of its (nonzero) digits is 1440, while the sum is 26.

Adding to 21221065106 its reverse (60156012212), we get a palindrome (81377077318).

It can be divided in two parts, 2122106 and 5106, that added together give a palindrome (2127212).

The spelling of 21221065106 in words is "twenty-one billion, two hundred twenty-one million, sixty-five thousand, one hundred six".