1221212010220 has 48 divisors (see below), whose sum is σ = 2662046368128. Its totient is φ = 470253922560.

The previous prime is 1221212010191. The next prime is 1221212010241. The reversal of 1221212010220 is 220102121221.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 1221212010194 and 1221212010203.

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, 10591527 + ... + 10706206.

It is an arithmetic number, because the mean of its divisors is an integer number (55459299336).

Almost surely, 2^{1221212010220} is an apocalyptic number.

1221212010220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221212010220 is an abundant number, since it is smaller than the sum of its proper divisors (1440834357908).

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

1221212010220 is a wasteful number, since it uses less digits than its factorization.

1221212010220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21297850 (or 21297848 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 1221212010220 its reverse (220102121221), we get a palindrome (1441314131441).

The spelling of 1221212010220 in words is "one trillion, two hundred twenty-one billion, two hundred twelve million, ten thousand, two hundred twenty".