121221020000 has 120 divisors (see below), whose sum is σ = 298908225000. Its totient is φ = 48376832000.

The previous prime is 121221019999. The next prime is 121221020009. The reversal of 121221020000 is 20122121.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221020009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 8973251 + ... + 8986749.

It is an arithmetic number, because the mean of its divisors is an integer number (2490901875).

Almost surely, 2^121221020000 is an apocalyptic number.

121221020000 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 121221020000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (149454112500).

121221020000 is an abundant number, since it is smaller than the sum of its proper divisors (177687205000).

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

121221020000 is an equidigital number, since it uses as much as digits as its factorization.

121221020000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13978 (or 13955 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 121221020000 its reverse (20122121), we get a palindrome (121241142121).

The spelling of 121221020000 in words is "one hundred twenty-one billion, two hundred twenty-one million, twenty thousand".