1221221120202 has 24 divisors (see below), whose sum is σ = 2646347535936. Its totient is φ = 407017023336.

The previous prime is 1221221120167. The next prime is 1221221120209. The reversal of 1221221120202 is 2020211221221.

It is a happy number.

1221221120202 is a `hidden beast` number, since 1 + 221 + 221 + 1 + 20 + 202 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (1221221120209) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4590658 + ... + 4849389.

It is an arithmetic number, because the mean of its divisors is an integer number (110264480664).

Almost surely, 2^{1221221120202} is an apocalyptic number.

1221221120202 is an abundant number, since it is smaller than the sum of its proper divisors (1425126415734).

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

1221221120202 is a wasteful number, since it uses less digits than its factorization.

1221221120202 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9447242 (or 9447239 counting only the distinct ones).

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

Adding to 1221221120202 its reverse (2020211221221), we get a palindrome (3241432341423).

The spelling of 1221221120202 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-one million, one hundred twenty thousand, two hundred two".