1221000102220 has 24 divisors (see below), whose sum is σ = 2573849656224. Its totient is φ = 486543004416.

The previous prime is 1221000102173. The next prime is 1221000102221. The reversal of 1221000102220 is 222010001221.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 1221000102220.

It is not an unprimeable number, because it can be changed into a prime (1221000102221) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 116059389 + ... + 116069908.

It is an arithmetic number, because the mean of its divisors is an integer number (107243735676).

Almost surely, 2^{1221000102220} is an apocalyptic number.

1221000102220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221000102220 is an abundant number, since it is smaller than the sum of its proper divisors (1352849554004).

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

1221000102220 is a wasteful number, since it uses less digits than its factorization.

1221000102220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 232129569 (or 232129567 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 13.

Adding to 1221000102220 its reverse (222010001221), we get a palindrome (1443010103441).

The spelling of 1221000102220 in words is "one trillion, two hundred twenty-one billion, one hundred two thousand, two hundred twenty".