1221312213000 has 768 divisors, whose sum is σ = 4779278899200. Its totient is φ = 278372160000.

The previous prime is 1221312212987. The next prime is 1221312213007. The reversal of 1221312213000 is 3122131221.

1221312213000 is a `hidden beast` number, since 1 + 221 + 312 + 2 + 130 + 0 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is not an unprimeable number, because it can be changed into a prime (1221312213007) by changing a digit.

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 191 ways as a sum of consecutive naturals, for example, 134338455 + ... + 134347545.

It is an arithmetic number, because the mean of its divisors is an integer number (6223019400).

Almost surely, 2^{1221312213000} is an apocalyptic number.

1221312213000 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 1221312213000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2389639449600).

1221312213000 is an abundant number, since it is smaller than the sum of its proper divisors (3557966686200).

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

1221312213000 is a wasteful number, since it uses less digits than its factorization.

1221312213000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9211 (or 9194 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 18.

Adding to 1221312213000 its reverse (3122131221), we get a palindrome (1224434344221).

The spelling of 1221312213000 in words is "one trillion, two hundred twenty-one billion, three hundred twelve million, two hundred thirteen thousand".