135240125261 has 2 divisors, whose sum is σ = 135240125262. Its totient is φ = 135240125260.

The previous prime is 135240125227. The next prime is 135240125269. The reversal of 135240125261 is 162521042531.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 76612704100 + 58627421161 = 276790^2 + 242131^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-135240125261 is a prime.

It is a super-2 number, since 2×135240125261² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (135240125269) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 67620062630 + 67620062631.

It is an arithmetic number, because the mean of its divisors is an integer number (67620062631).

Almost surely, 2^135240125261 is an apocalyptic number.

It is an amenable number.

135240125261 is a deficient number, since it is larger than the sum of its proper divisors (1).

135240125261 is an equidigital number, since it uses as much as digits as its factorization.

135240125261 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 14400, while the sum is 32.

Adding to 135240125261 its reverse (162521042531), we get a palindrome (297761167792).

The spelling of 135240125261 in words is "one hundred thirty-five billion, two hundred forty million, one hundred twenty-five thousand, two hundred sixty-one".