121000221 has 6 divisors (see below), whose sum is σ = 174778110. Its totient is φ = 80666808.

The previous prime is 121000213. The next prime is 121000261. The reversal of 121000221 is 122000121.

It can be written as a sum of positive squares in only one way, i.e., 120692196 + 308025 = 10986^2 + 555^2 .

It is not a de Polignac number, because 121000221 - 2³ = 121000213 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9), and also a Moran number because the ratio is a prime number: 13444469 = 121000221 / (1 + 2 + 1 + 0 + 0 + 0 + 2 + 2 + 1).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121000211) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6722226 + ... + 6722243.

It is an arithmetic number, because the mean of its divisors is an integer number (29129685).

Almost surely, 2^121000221 is an apocalyptic number.

It is an amenable number.

121000221 is a deficient number, since it is larger than the sum of its proper divisors (53777889).

121000221 is a wasteful number, since it uses less digits than its factorization.

121000221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13444475 (or 13444472 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 121000221 is about 11000.0100454500. The cubic root of 121000221 is about 494.6090454501.

Adding to 121000221 its reverse (122000121), we get a palindrome (243000342).

The spelling of 121000221 in words is "one hundred twenty-one million, two hundred twenty-one", and thus it is an aban number.