1221002221200 has 240 divisors, whose sum is σ = 4128200450880. Its totient is φ = 307634595840.

The previous prime is 1221002221169. The next prime is 1221002221223. The reversal of 1221002221200 is 21222001221.

It is a tau number, because it is divible by the number of its divisors (240).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 1221002221200.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 8432614 + ... + 8576186.

It is an arithmetic number, because the mean of its divisors is an integer number (17200835212).

Almost surely, 2^{1221002221200} is an apocalyptic number.

1221002221200 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 1221002221200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2064100225440).

1221002221200 is an abundant number, since it is smaller than the sum of its proper divisors (2907198229680).

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

1221002221200 is a wasteful number, since it uses less digits than its factorization.

1221002221200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 143986 (or 143975 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 1221002221200 its reverse (21222001221), we get a palindrome (1242224222421).

The spelling of 1221002221200 in words is "one trillion, two hundred twenty-one billion, two million, two hundred twenty-one thousand, two hundred".