135731 has 2 divisors, whose sum is σ = 135732. Its totient is φ = 135730.

The previous prime is 135727. The next prime is 135743. The reversal of 135731 is 137531.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 135731 - 2² = 135727 is a prime.

It is a super-2 number, since 2×135731² = 36845808722, which contains 22 as substring.

It is a Sophie Germain prime.

It is equal to p₁₂₆₄₇ and since 135731 and 12647 have the same sum of digits, it is a Honaker prime.

It is a plaindrome in base 12.

It is not a weakly prime, because it can be changed into another prime (135701) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 67865 + 67866.

It is an arithmetic number, because the mean of its divisors is an integer number (67866).

2¹³⁵⁷³¹ is an apocalyptic number.

135731 is a deficient number, since it is larger than the sum of its proper divisors (1).

135731 is an equidigital number, since it uses as much as digits as its factorization.

135731 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 315, while the sum is 20.

The square root of 135731 is about 368.4168834351. The cubic root of 135731 is about 51.3917038092.

The spelling of 135731 in words is "one hundred thirty-five thousand, seven hundred thirty-one".