121221100213 has 8 divisors (see below), whose sum is σ = 123314909400. Its totient is φ = 119144812800.

The previous prime is 121221100183. The next prime is 121221100223. The reversal of 121221100213 is 312001122121.

It can be written as a sum of positive squares in 4 ways, for example, as 84179478769 + 37041621444 = 290137^2 + 192462^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 121221100213 - 2²⁹ = 120684229301 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121221100223) 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, 4366488 + ... + 4394161.

It is an arithmetic number, because the mean of its divisors is an integer number (15414363675).

Almost surely, 2^121221100213 is an apocalyptic number.

It is an amenable number.

121221100213 is a deficient number, since it is larger than the sum of its proper divisors (2093809187).

121221100213 is a wasteful number, since it uses less digits than its factorization.

121221100213 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8760887.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 121221100213 its reverse (312001122121), we get a palindrome (433222222334).

The spelling of 121221100213 in words is "one hundred twenty-one billion, two hundred twenty-one million, one hundred thousand, two hundred thirteen".