1221011022220 has 48 divisors (see below), whose sum is σ = 2811281760000. Its totient is φ = 441772816320.

The previous prime is 1221011022167. The next prime is 1221011022239. The reversal of 1221011022220 is 222201101221.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 1221011022194 and 1221011022203.

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 15 ways as a sum of consecutive naturals, for example, 13901070 + ... + 13988629.

It is an arithmetic number, because the mean of its divisors is an integer number (58568370000).

Almost surely, 2^{1221011022220} is an apocalyptic number.

1221011022220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221011022220 is an abundant number, since it is smaller than the sum of its proper divisors (1590270737780).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1221011022220 is a wasteful number, since it uses less digits than its factorization.

1221011022220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27889918 (or 27889916 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 1221011022220 its reverse (222201101221), we get a palindrome (1443212123441).

The spelling of 1221011022220 in words is "one trillion, two hundred twenty-one billion, eleven million, twenty-two thousand, two hundred twenty".