135545435444021 has 4 divisors (see below), whose sum is σ = 135547040813292. Its totient is φ = 135543830074752.

The previous prime is 135545435444011. The next prime is 135545435444039. The reversal of 135545435444021 is 120444534545531.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 121642149722500 + 13903285721521 = 11029150^2 + 3728711^2 .

It is a cyclic number.

It is not a de Polignac number, because 135545435444021 - 2²² = 135545431249717 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135545435444011) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 802557980 + ... + 802726853.

It is an arithmetic number, because the mean of its divisors is an integer number (33886760203323).

Almost surely, 2^{135545435444021} is an apocalyptic number.

It is an amenable number.

135545435444021 is a deficient number, since it is larger than the sum of its proper divisors (1605369271).

135545435444021 is an equidigital number, since it uses as much as digits as its factorization.

135545435444021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1605369270.

The product of its (nonzero) digits is 11520000, while the sum is 50.

Adding to 135545435444021 its reverse (120444534545531), we get a palindrome (255989969989552).

The spelling of 135545435444021 in words is "one hundred thirty-five trillion, five hundred forty-five billion, four hundred thirty-five million, four hundred forty-four thousand, twenty-one".