1221221021210 has 16 divisors (see below), whose sum is σ = 2313892461600. Its totient is φ = 462778492176.

The previous prime is 1221221021173. The next prime is 1221221021219. The reversal of 1221221021210 is 121201221221.

It is not an unprimeable number, because it can be changed into a prime (1221221021219) 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, 3213739340 + ... + 3213739719.

It is an arithmetic number, because the mean of its divisors is an integer number (144618278850).

Almost surely, 2^{1221221021210} is an apocalyptic number.

1221221021210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1221221021210 is a deficient number, since it is larger than the sum of its proper divisors (1092671440390).

1221221021210 is a wasteful number, since it uses less digits than its factorization.

1221221021210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6427479085.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 1221221021210 its reverse (121201221221), we get a palindrome (1342422242431).

The spelling of 1221221021210 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-one million, twenty-one thousand, two hundred ten".