1200012221100 has 288 divisors, whose sum is σ = 4330763813376. Its totient is φ = 249238425600.

The previous prime is 1200012221081. The next prime is 1200012221101. The reversal of 1200012221100 is 11222100021.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (1200012221101) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 55821954 + ... + 55843446.

It is an arithmetic number, because the mean of its divisors is an integer number (15037374352).

Almost surely, 2^{1200012221100} is an apocalyptic number.

1200012221100 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 1200012221100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2165381906688).

1200012221100 is an abundant number, since it is smaller than the sum of its proper divisors (3130751592276).

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

1200012221100 is a wasteful number, since it uses less digits than its factorization.

1200012221100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23945 (or 23938 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 1200012221100 its reverse (11222100021), we get a palindrome (1211234321121).

The spelling of 1200012221100 in words is "one trillion, two hundred billion, twelve million, two hundred twenty-one thousand, one hundred".