21221121222110 has 16 divisors (see below), whose sum is σ = 38576216401632. Its totient is φ = 8404404444000.

The previous prime is 21221121222101. The next prime is 21221121222113. The reversal of 21221121222110 is 1122212112212.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221121222113) 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, 10505504546 + ... + 10505506565.

It is an arithmetic number, because the mean of its divisors is an integer number (2411013525102).

Almost surely, 2^{21221121222110} is an apocalyptic number.

21221121222110 is a deficient number, since it is larger than the sum of its proper divisors (17355095179522).

21221121222110 is a wasteful number, since it uses less digits than its factorization.

21221121222110 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21011011219.

The product of its (nonzero) digits is 128, while the sum is 20.

Adding to 21221121222110 its reverse (1122212112212), we get a palindrome (22343333334322).

The spelling of 21221121222110 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred twenty-one million, two hundred twenty-two thousand, one hundred ten".