135398337821 has 2 divisors, whose sum is σ = 135398337822. Its totient is φ = 135398337820.

The previous prime is 135398337799. The next prime is 135398337839. The reversal of 135398337821 is 128733893531.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 101987616025 + 33410721796 = 319355^2 + 182786^2 .

It is a cyclic number.

It is not a de Polignac number, because 135398337821 - 2³⁰ = 134324595997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (135398337881) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 67699168910 + 67699168911.

It is an arithmetic number, because the mean of its divisors is an integer number (67699168911).

Almost surely, 2^135398337821 is an apocalyptic number.

It is an amenable number.

135398337821 is a deficient number, since it is larger than the sum of its proper divisors (1).

135398337821 is an equidigital number, since it uses as much as digits as its factorization.

135398337821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3265920, while the sum is 53.

The spelling of 135398337821 in words is "one hundred thirty-five billion, three hundred ninety-eight million, three hundred thirty-seven thousand, eight hundred twenty-one".