121121221221210 has 128 divisors (see below), whose sum is σ = 333680643072000. Its totient is φ = 27563031175680.

The previous prime is 121121221221193. The next prime is 121121221221239. The reversal of 121121221221210 is 12122122121121.

It is a super-3 number, since 3×121121221221210³ (a number of 43 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 233073765 + ... + 233592855.

It is an arithmetic number, because the mean of its divisors is an integer number (2606880024000).

Almost surely, 2^{121121221221210} is an apocalyptic number.

121121221221210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 121121221221210, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (166840321536000).

121121221221210 is an abundant number, since it is smaller than the sum of its proper divisors (212559421850790).

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

121121221221210 is a wasteful number, since it uses less digits than its factorization.

121121221221210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 523996.

The product of its (nonzero) digits is 128, while the sum is 21.

Adding to 121121221221210 its reverse (12122122121121), we get a palindrome (133243343342331).

The spelling of 121121221221210 in words is "one hundred twenty-one trillion, one hundred twenty-one billion, two hundred twenty-one million, two hundred twenty-one thousand, two hundred ten".