121242521400 has 768 divisors, whose sum is σ = 522116582400. Its totient is φ = 22450176000.

The previous prime is 121242521381. The next prime is 121242521401. The reversal of 121242521400 is 4125242121.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121242521401) 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 191 ways as a sum of consecutive naturals, for example, 17413920 + ... + 17420880.

It is an arithmetic number, because the mean of its divisors is an integer number (679839300).

Almost surely, 2^121242521400 is an apocalyptic number.

121242521400 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 121242521400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (261058291200).

121242521400 is an abundant number, since it is smaller than the sum of its proper divisors (400874061000).

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

121242521400 is a wasteful number, since it uses less digits than its factorization.

121242521400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7040 (or 7031 counting only the distinct ones).

The product of its (nonzero) digits is 1280, while the sum is 24.

Adding to 121242521400 its reverse (4125242121), we get a palindrome (125367763521).

The spelling of 121242521400 in words is "one hundred twenty-one billion, two hundred forty-two million, five hundred twenty-one thousand, four hundred".