1213220121000 has 384 divisors, whose sum is σ = 3949275657600. Its totient is φ = 310012876800.

The previous prime is 1213220120993. The next prime is 1213220121013. The reversal of 1213220121000 is 1210223121.

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

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 275166796 + ... + 275171204.

It is an arithmetic number, because the mean of its divisors is an integer number (10284572025).

Almost surely, 2^{1213220121000} is an apocalyptic number.

1213220121000 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 1213220121000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1974637828800).

1213220121000 is an abundant number, since it is smaller than the sum of its proper divisors (2736055536600).

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

1213220121000 is a wasteful number, since it uses less digits than its factorization.

1213220121000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4574 (or 4523 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 1213220121000 its reverse (1210223121), we get a palindrome (1214430344121).

The spelling of 1213220121000 in words is "one trillion, two hundred thirteen billion, two hundred twenty million, one hundred twenty-one thousand".