101221000000000 has 200 divisors, whose sum is σ = 252807850089036. Its totient is φ = 40488000000000.

The previous prime is 101220999999991. The next prime is 101221000000033. The reversal of 101221000000000 is 122101.

It can be written as a sum of positive squares in 10 ways, for example, as 32654915944704 + 68566084055296 = 5714448^2 + 8280464^2 .

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

It is a self number, because there is not a number n which added to its sum of digits gives 101221000000000.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 999949390 + ... + 1000050610.

Almost surely, 2^{101221000000000} is an apocalyptic number.

101221000000000 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 101221000000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (126403925044518).

101221000000000 is an abundant number, since it is smaller than the sum of its proper divisors (151586850089036).

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

101221000000000 is an frugal number, since it uses more digits than its factorization.

101221000000000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 101284 (or 101228 counting only the distinct ones).

The product of its (nonzero) digits is 4, while the sum is 7.

Adding to 101221000000000 its reverse (122101), we get a palindrome (101221000122101).

The spelling of 101221000000000 in words is "one hundred one trillion, two hundred twenty-one billion", and thus it is an aban number.