135075821 has 2 divisors, whose sum is σ = 135075822. Its totient is φ = 135075820.

The previous prime is 135075817. The next prime is 135075833. The reversal of 135075821 is 128570531.

135075821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 88153321 + 46922500 = 9389^2 + 6850^2 .

It is an emirp because it is prime and its reverse (128570531) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 135075821 - 2² = 135075817 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 (135075841) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 67537910 + 67537911.

It is an arithmetic number, because the mean of its divisors is an integer number (67537911).

Almost surely, 2^135075821 is an apocalyptic number.

It is an amenable number.

135075821 is a deficient number, since it is larger than the sum of its proper divisors (1).

135075821 is an equidigital number, since it uses as much as digits as its factorization.

135075821 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8400, while the sum is 32.

The square root of 135075821 is about 11622.2123969578. The cubic root of 135075821 is about 513.0888046114.

The spelling of 135075821 in words is "one hundred thirty-five million, seventy-five thousand, eight hundred twenty-one".