135215261 has 2 divisors, whose sum is σ = 135215262. Its totient is φ = 135215260.

The previous prime is 135215239. The next prime is 135215281. The reversal of 135215261 is 162512531.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 101505625 + 33709636 = 10075^2 + 5806^2 .

It is a cyclic number.

It is not a de Polignac number, because 135215261 - 2¹⁰ = 135214237 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 135215261.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (135215231) 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, 67607630 + 67607631.

It is an arithmetic number, because the mean of its divisors is an integer number (67607631).

Almost surely, 2^135215261 is an apocalyptic number.

It is an amenable number.

135215261 is a deficient number, since it is larger than the sum of its proper divisors (1).

135215261 is an equidigital number, since it uses as much as digits as its factorization.

135215261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1800, while the sum is 26.

The square root of 135215261 is about 11628.2097074313. The cubic root of 135215261 is about 513.2652993080.

Adding to 135215261 its reverse (162512531), we get a palindrome (297727792).

The spelling of 135215261 in words is "one hundred thirty-five million, two hundred fifteen thousand, two hundred sixty-one".