1021212221220 has 96 divisors (see below), whose sum is σ = 3177356595840. Its totient is φ = 272301667200.

The previous prime is 1021212221207. The next prime is 1021212221231. The reversal of 1021212221220 is 221222121201.

It is a happy number.

1021212221220 is a `hidden beast` number, since 1 + 0 + 212 + 12 + 221 + 220 = 666.

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 = 1021212221193 and 1021212221202.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7438519 + ... + 7574561.

It is an arithmetic number, because the mean of its divisors is an integer number (33097464540).

Almost surely, 2^{1021212221220} is an apocalyptic number.

1021212221220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1021212221220 is an abundant number, since it is smaller than the sum of its proper divisors (2156144374620).

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

1021212221220 is a wasteful number, since it uses less digits than its factorization.

1021212221220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149962 (or 149954 counting only the distinct ones).

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

Adding to 1021212221220 its reverse (221222121201), we get a palindrome (1242434342421).

The spelling of 1021212221220 in words is "one trillion, twenty-one billion, two hundred twelve million, two hundred twenty-one thousand, two hundred twenty".