1021222121220 has 108 divisors (see below), whose sum is σ = 3603455230284. Its totient is φ = 233422197120.

The previous prime is 1021222121219. The next prime is 1021222121287. The reversal of 1021222121220 is 221212221201.

It is a happy number.

1021222121220 is a `hidden beast` number, since 1 + 0 + 212 + 221 + 212 + 20 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 588681769536 + 432540351684 = 767256^2 + 657678^2 .

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 = 1021222121193 and 1021222121202.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 57883591 + ... + 57901230.

Almost surely, 2^{1021222121220} is an apocalyptic number.

1021222121220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1021222121220 is an abundant number, since it is smaller than the sum of its proper divisors (2582233109064).

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

1021222121220 is a wasteful number, since it uses less digits than its factorization.

1021222121220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115784850 (or 115784838 counting only the distinct ones).

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

Adding to 1021222121220 its reverse (221212221201), we get a palindrome (1242434342421).

The spelling of 1021222121220 in words is "one trillion, twenty-one billion, two hundred twenty-two million, one hundred twenty-one thousand, two hundred twenty".