121721203 has 2 divisors, whose sum is σ = 121721204. Its totient is φ = 121721202.

The previous prime is 121721191. The next prime is 121721209. The reversal of 121721203 is 302127121.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 121721203 - 2²¹ = 119624051 is a prime.

It is not a weakly prime, because it can be changed into another prime (121721209) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 60860601 + 60860602.

It is an arithmetic number, because the mean of its divisors is an integer number (60860602).

Almost surely, 2^121721203 is an apocalyptic number.

121721203 is a deficient number, since it is larger than the sum of its proper divisors (1).

121721203 is an equidigital number, since it uses as much as digits as its factorization.

121721203 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 168, while the sum is 19.

The square root of 121721203 is about 11032.7332515565. The cubic root of 121721203 is about 495.5894796830.

Adding to 121721203 its reverse (302127121), we get a palindrome (423848324).

The spelling of 121721203 in words is "one hundred twenty-one million, seven hundred twenty-one thousand, two hundred three".