121090021 has 24 divisors (see below), whose sum is σ = 141393120. Its totient is φ = 103311936.

The previous prime is 121090019. The next prime is 121090033. The reversal of 121090021 is 120090121.

It is not a de Polignac number, because 121090021 - 2¹ = 121090019 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 121089977 and 121090004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121090091) 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 23 ways as a sum of consecutive naturals, for example, 137635 + ... + 138511.

It is an arithmetic number, because the mean of its divisors is an integer number (5891380).

Almost surely, 2^121090021 is an apocalyptic number.

It is an amenable number.

121090021 is a deficient number, since it is larger than the sum of its proper divisors (20303099).

121090021 is a wasteful number, since it uses less digits than its factorization.

121090021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 965 (or 952 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 16.

The square root of 121090021 is about 11004.0911028581. The cubic root of 121090021 is about 494.7313728000.

The spelling of 121090021 in words is "one hundred twenty-one million, ninety thousand, twenty-one".