135511531 has 2 divisors, whose sum is σ = 135511532. Its totient is φ = 135511530.

The previous prime is 135511529. The next prime is 135511543. The reversal of 135511531 is 135115531.

It is a happy number.

It is a weak prime.

It is an emirp because it is prime and its reverse (135115531) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 135511531 - 2¹ = 135511529 is a prime.

It is a super-2 number, since 2×135511531² = 36726750067927922, which contains 22 as substring.

Together with 135511529, it forms a pair of twin primes.

It is a junction number, because it is equal to n+sod(n) for n = 135511496 and 135511505.

It is not a weakly prime, because it can be changed into another prime (135511511) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 67755765 + 67755766.

It is an arithmetic number, because the mean of its divisors is an integer number (67755766).

Almost surely, 2^135511531 is an apocalyptic number.

135511531 is a deficient number, since it is larger than the sum of its proper divisors (1).

135511531 is an equidigital number, since it uses as much as digits as its factorization.

135511531 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1125, while the sum is 25.

The square root of 135511531 is about 11640.9420151464. The cubic root of 135511531 is about 513.6398975126.

The spelling of 135511531 in words is "one hundred thirty-five million, five hundred eleven thousand, five hundred thirty-one".