1221512010000 has 200 divisors, whose sum is σ = 3944666852544. Its totient is φ = 325615680000.

The previous prime is 1221512009987. The next prime is 1221512010011. The reversal of 1221512010000 is 102151221.

It is a tau number, because it is divible by the number of its divisors (200).

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

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 105324202 + ... + 105335798.

Almost surely, 2^{1221512010000} is an apocalyptic number.

1221512010000 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 1221512010000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1972333426272).

1221512010000 is an abundant number, since it is smaller than the sum of its proper divisors (2723154842544).

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

1221512010000 is a wasteful number, since it uses less digits than its factorization.

1221512010000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15139 (or 15118 counting only the distinct ones).

The product of its (nonzero) digits is 40, while the sum is 15.

Adding to 1221512010000 its reverse (102151221), we get a palindrome (1221614161221).

The spelling of 1221512010000 in words is "one trillion, two hundred twenty-one billion, five hundred twelve million, ten thousand".