121221020202109 has 16 divisors (see below), whose sum is σ = 123350955293440. Its totient is φ = 119109940646400.

The previous prime is 121221020202089. The next prime is 121221020202133. The reversal of 121221020202109 is 901202020122121.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 121221020202109 - 2⁹ = 121221020201597 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 (121221020202209) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23794747 + ... + 28436455.

It is an arithmetic number, because the mean of its divisors is an integer number (7709434705840).

Almost surely, 2^{121221020202109} is an apocalyptic number.

It is an amenable number.

121221020202109 is a deficient number, since it is larger than the sum of its proper divisors (2129935091331).

121221020202109 is a wasteful number, since it uses less digits than its factorization.

121221020202109 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4643740.

The product of its (nonzero) digits is 576, while the sum is 25.

The spelling of 121221020202109 in words is "one hundred twenty-one trillion, two hundred twenty-one billion, twenty million, two hundred two thousand, one hundred nine".