121221012210 has 16 divisors (see below), whose sum is σ = 290930429376. Its totient is φ = 32325603248.

The previous prime is 121221012197. The next prime is 121221012217. The reversal of 121221012210 is 12210122121.

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

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 121221012210.

It is not an unprimeable number, because it can be changed into a prime (121221012217) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2020350174 + ... + 2020350233.

It is an arithmetic number, because the mean of its divisors is an integer number (18183151836).

Almost surely, 2^121221012210 is an apocalyptic number.

121221012210 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

121221012210 is an abundant number, since it is smaller than the sum of its proper divisors (169709417166).

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

121221012210 is a wasteful number, since it uses less digits than its factorization.

121221012210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4040700417.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 121221012210 its reverse (12210122121), we get a palindrome (133431134331).

The spelling of 121221012210 in words is "one hundred twenty-one billion, two hundred twenty-one million, twelve thousand, two hundred ten".