1221122212020 has 72 divisors (see below), whose sum is σ = 3782880751104. Its totient is φ = 318704234688.

The previous prime is 1221122212003. The next prime is 1221122212043. The reversal of 1221122212020 is 202122211221.

It is a happy number.

It is a super-2 number, since 2×1221122212020² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 1221122211984 and 1221122212002.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 72161884 + ... + 72178803.

It is an arithmetic number, because the mean of its divisors is an integer number (52540010432).

Almost surely, 2^{1221122212020} is an apocalyptic number.

1221122212020 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221122212020 is an abundant number, since it is smaller than the sum of its proper divisors (2561758539084).

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

1221122212020 is a wasteful number, since it uses less digits than its factorization.

1221122212020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 144340749 (or 144340744 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

Adding to 1221122212020 its reverse (202122211221), we get a palindrome (1423244423241).

The spelling of 1221122212020 in words is "one trillion, two hundred twenty-one billion, one hundred twenty-two million, two hundred twelve thousand, twenty".