201115121 has 2 divisors, whose sum is σ = 201115122. Its totient is φ = 201115120.

The previous prime is 201115111. The next prime is 201115153. The reversal of 201115121 is 121511102.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 198669025 + 2446096 = 14095^2 + 1564^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-201115121 is a prime.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 201115096 and 201115105.

It is not a weakly prime, because it can be changed into another prime (201115111) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 100557560 + 100557561.

It is an arithmetic number, because the mean of its divisors is an integer number (100557561).

Almost surely, 2^201115121 is an apocalyptic number.

It is an amenable number.

201115121 is a deficient number, since it is larger than the sum of its proper divisors (1).

201115121 is an equidigital number, since it uses as much as digits as its factorization.

201115121 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20, while the sum is 14.

The square root of 201115121 is about 14181.5063022233. The cubic root of 201115121 is about 585.8884117374. Note that the first 3 decimals are identical.

Adding to 201115121 its reverse (121511102), we get a palindrome (322626223).

The spelling of 201115121 in words is "two hundred one million, one hundred fifteen thousand, one hundred twenty-one".