135540989 has 2 divisors, whose sum is σ = 135540990. Its totient is φ = 135540988.

The previous prime is 135540973. The next prime is 135540991. The reversal of 135540989 is 989045531.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 135256900 + 284089 = 11630^2 + 533^2 .

It is a cyclic number.

It is not a de Polignac number, because 135540989 - 2⁴ = 135540973 is a prime.

Together with 135540991, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (135540929) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 67770494 + 67770495.

It is an arithmetic number, because the mean of its divisors is an integer number (67770495).

Almost surely, 2^135540989 is an apocalyptic number.

It is an amenable number.

135540989 is a deficient number, since it is larger than the sum of its proper divisors (1).

135540989 is an equidigital number, since it uses as much as digits as its factorization.

135540989 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 194400, while the sum is 44.

The square root of 135540989 is about 11642.2072220005. The cubic root of 135540989 is about 513.6771137990.

The spelling of 135540989 in words is "one hundred thirty-five million, five hundred forty thousand, nine hundred eighty-nine".