135821489 has 2 divisors, whose sum is σ = 135821490. Its totient is φ = 135821488.

The previous prime is 135821473. The next prime is 135821573. The reversal of 135821489 is 984128531.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 133287025 + 2534464 = 11545^2 + 1592^2 .

It is a cyclic number.

It is not a de Polignac number, because 135821489 - 2⁴ = 135821473 is a prime.

It is not a weakly prime, because it can be changed into another prime (135821429) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 67910744 + 67910745.

It is an arithmetic number, because the mean of its divisors is an integer number (67910745).

Almost surely, 2^135821489 is an apocalyptic number.

It is an amenable number.

135821489 is a deficient number, since it is larger than the sum of its proper divisors (1).

135821489 is an equidigital number, since it uses as much as digits as its factorization.

135821489 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 69120, while the sum is 41.

The square root of 135821489 is about 11654.2476805669. The cubic root of 135821489 is about 514.0312186119.

The spelling of 135821489 in words is "one hundred thirty-five million, eight hundred twenty-one thousand, four hundred eighty-nine".