1221210012000 has 384 divisors, whose sum is σ = 4482356755968. Its totient is φ = 288048384000.

The previous prime is 1221210011993. The next prime is 1221210012007. The reversal of 1221210012000 is 2100121221.

It is an interprime number because it is at equal distance from previous prime (1221210011993) and next prime (1221210012007).

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221210012007) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 4758979 + ... + 5009021.

It is an arithmetic number, because the mean of its divisors is an integer number (11672804052).

Almost surely, 2^{1221210012000} is an apocalyptic number.

1221210012000 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 1221210012000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2241178377984).

1221210012000 is an abundant number, since it is smaller than the sum of its proper divisors (3261146743968).

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

1221210012000 is a wasteful number, since it uses less digits than its factorization.

1221210012000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250119 (or 250101 counting only the distinct ones).

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

Adding to 1221210012000 its reverse (2100121221), we get a palindrome (1223310133221).

The spelling of 1221210012000 in words is "one trillion, two hundred twenty-one billion, two hundred ten million, twelve thousand".