135528781 has 2 divisors, whose sum is σ = 135528782. Its totient is φ = 135528780.

The previous prime is 135528779. The next prime is 135528787. The reversal of 135528781 is 187825531.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 133749225 + 1779556 = 11565^2 + 1334^2 .

It is an emirp because it is prime and its reverse (187825531) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 135528781 - 2¹ = 135528779 is a prime.

It is a super-2 number, since 2×135528781² = 36736100958691922, which contains 22 as substring.

Together with 135528779, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (135528787) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 67764390 + 67764391.

It is an arithmetic number, because the mean of its divisors is an integer number (67764391).

Almost surely, 2^135528781 is an apocalyptic number.

It is an amenable number.

135528781 is a deficient number, since it is larger than the sum of its proper divisors (1).

135528781 is an equidigital number, since it uses as much as digits as its factorization.

135528781 is an evil number, because the sum of its binary digits is even.

The product of its digits is 67200, while the sum is 40.

The square root of 135528781 is about 11641.6829109884. The cubic root of 135528781 is about 513.6616912601.

The spelling of 135528781 in words is "one hundred thirty-five million, five hundred twenty-eight thousand, seven hundred eighty-one".