1221112222220 has 48 divisors (see below), whose sum is σ = 2801890780416. Its totient is φ = 443337048000.

The previous prime is 1221112222153. The next prime is 1221112222249. The reversal of 1221112222220 is 222222111221.

It is a super-2 number, since 2×1221112222220² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 1221112222192 and 1221112222201.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4259366 + ... + 4537005.

It is an arithmetic number, because the mean of its divisors is an integer number (58372724592).

Almost surely, 2^{1221112222220} is an apocalyptic number.

1221112222220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221112222220 is an abundant number, since it is smaller than the sum of its proper divisors (1580778558196).

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

1221112222220 is a wasteful number, since it uses less digits than its factorization.

1221112222220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8797022 (or 8797020 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 1221112222220 its reverse (222222111221), we get a palindrome (1443334333441).

The spelling of 1221112222220 in words is "one trillion, two hundred twenty-one billion, one hundred twelve million, two hundred twenty-two thousand, two hundred twenty".