231202121 has 2 divisors, whose sum is σ = 231202122. Its totient is φ = 231202120.

The previous prime is 231202093. The next prime is 231202171. The reversal of 231202121 is 121202132.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 216678400 + 14523721 = 14720^2 + 3811^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-231202121 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 231202096 and 231202105.

It is not a weakly prime, because it can be changed into another prime (231202171) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 115601060 + 115601061.

It is an arithmetic number, because the mean of its divisors is an integer number (115601061).

Almost surely, 2^231202121 is an apocalyptic number.

It is an amenable number.

231202121 is a deficient number, since it is larger than the sum of its proper divisors (1).

231202121 is an equidigital number, since it uses as much as digits as its factorization.

231202121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48, while the sum is 14.

The square root of 231202121 is about 15205.3319924295. The cubic root of 231202121 is about 613.7581488680.

Adding to 231202121 its reverse (121202132), we get a palindrome (352404253).

The spelling of 231202121 in words is "two hundred thirty-one million, two hundred two thousand, one hundred twenty-one".