135115021 has 2 divisors, whose sum is σ = 135115022. Its totient is φ = 135115020.

The previous prime is 135115003. The next prime is 135115027. The reversal of 135115021 is 120511531.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 123520996 + 11594025 = 11114^2 + 3405^2 .

It is a cyclic number.

It is not a de Polignac number, because 135115021 - 2⁷ = 135114893 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 135115021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (135115027) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 67557510 + 67557511.

It is an arithmetic number, because the mean of its divisors is an integer number (67557511).

Almost surely, 2^135115021 is an apocalyptic number.

It is an amenable number.

135115021 is a deficient number, since it is larger than the sum of its proper divisors (1).

135115021 is an equidigital number, since it uses as much as digits as its factorization.

135115021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 150, while the sum is 19.

The square root of 135115021 is about 11623.8987005221. The cubic root of 135115021 is about 513.1384338632.

Adding to 135115021 its reverse (120511531), we get a palindrome (255626552).

The spelling of 135115021 in words is "one hundred thirty-five million, one hundred fifteen thousand, twenty-one".