1221102321200 has 120 divisors (see below), whose sum is σ = 3035657156400. Its totient is φ = 471720775680.

The previous prime is 1221102321191. The next prime is 1221102321209. The reversal of 1221102321200 is 21232011221.

It is an interprime number because it is at equal distance from previous prime (1221102321191) and next prime (1221102321209).

It is not an unprimeable number, because it can be changed into a prime (1221102321209) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1131956 + ... + 1929644.

It is an arithmetic number, because the mean of its divisors is an integer number (25297142970).

Almost surely, 2^{1221102321200} is an apocalyptic number.

1221102321200 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1221102321200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1517828578200).

1221102321200 is an abundant number, since it is smaller than the sum of its proper divisors (1814554835200).

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

1221102321200 is a wasteful number, since it uses less digits than its factorization.

1221102321200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 797839 (or 797828 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 17.

Adding to 1221102321200 its reverse (21232011221), we get a palindrome (1242334332421).

The spelling of 1221102321200 in words is "one trillion, two hundred twenty-one billion, one hundred two million, three hundred twenty-one thousand, two hundred".