135989221 has 2 divisors, whose sum is σ = 135989222. Its totient is φ = 135989220.

The previous prime is 135989201. The next prime is 135989261. The reversal of 135989221 is 122989531.

It is an a-pointer prime, because the next prime (135989261) can be obtained adding 135989221 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 129072321 + 6916900 = 11361^2 + 2630^2 .

It is a cyclic number.

It is not a de Polignac number, because 135989221 - 2²⁵ = 102434789 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (135989201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 67994610 + 67994611.

It is an arithmetic number, because the mean of its divisors is an integer number (67994611).

Almost surely, 2^135989221 is an apocalyptic number.

It is an amenable number.

135989221 is a deficient number, since it is larger than the sum of its proper divisors (1).

135989221 is an equidigital number, since it uses as much as digits as its factorization.

135989221 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 38880, while the sum is 40.

The square root of 135989221 is about 11661.4416347208. The cubic root of 135989221 is about 514.2427315745.

The spelling of 135989221 in words is "one hundred thirty-five million, nine hundred eighty-nine thousand, two hundred twenty-one".