1221101101220 has 96 divisors (see below), whose sum is σ = 3442992811776. Its totient is φ = 351325785600.

The previous prime is 1221101101169. The next prime is 1221101101229. The reversal of 1221101101220 is 221011011221.

It is a Harshad number since it is a multiple of its sum of digits (14).

It is a junction number, because it is equal to n+sod(n) for n = 1221101101195 and 1221101101204.

It is not an unprimeable number, because it can be changed into a prime (1221101101229) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 30477011 + ... + 30517050.

It is an arithmetic number, because the mean of its divisors is an integer number (35864508456).

Almost surely, 2^{1221101101220} is an apocalyptic number.

1221101101220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221101101220 is an abundant number, since it is smaller than the sum of its proper divisors (2221891710556).

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

1221101101220 is a wasteful number, since it uses less digits than its factorization.

1221101101220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60994101 (or 60994099 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 1221101101220 its reverse (221011011221), we get a palindrome (1442112112441).

The spelling of 1221101101220 in words is "one trillion, two hundred twenty-one billion, one hundred one million, one hundred one thousand, two hundred twenty".