121938221 has 4 divisors (see below), whose sum is σ = 125871744. Its totient is φ = 118004700.

The previous prime is 121938217. The next prime is 121938233. The reversal of 121938221 is 122839121.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 122839121 = 59 ⋅2082019.

It is a cyclic number.

It is not a de Polignac number, because 121938221 - 2² = 121938217 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (121938211) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1966715 + ... + 1966776.

It is an arithmetic number, because the mean of its divisors is an integer number (31467936).

Almost surely, 2^121938221 is an apocalyptic number.

It is an amenable number.

121938221 is a deficient number, since it is larger than the sum of its proper divisors (3933523).

121938221 is an equidigital number, since it uses as much as digits as its factorization.

121938221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3933522.

The product of its digits is 1728, while the sum is 29.

The square root of 121938221 is about 11042.5640591305. The cubic root of 121938221 is about 495.8838353632.

The spelling of 121938221 in words is "one hundred twenty-one million, nine hundred thirty-eight thousand, two hundred twenty-one".