135436064221 has 4 divisors (see below), whose sum is σ = 135438973852. Its totient is φ = 135433154592.

The previous prime is 135436064201. The next prime is 135436064237. The reversal of 135436064221 is 122460634531.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 122460634531 = 1031 ⋅118778501.

It can be written as a sum of positive squares in 2 ways, for example, as 119657187225 + 15778876996 = 345915^2 + 125614^2 .

It is a cyclic number.

It is not a de Polignac number, because 135436064221 - 2¹³ = 135436056029 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 (135436064201) 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, 1383840 + ... + 1478473.

It is an arithmetic number, because the mean of its divisors is an integer number (33859743463).

Almost surely, 2^135436064221 is an apocalyptic number.

It is an amenable number.

135436064221 is a deficient number, since it is larger than the sum of its proper divisors (2909631).

135436064221 is an equidigital number, since it uses as much as digits as its factorization.

135436064221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2909630.

The product of its (nonzero) digits is 103680, while the sum is 37.

Adding to 135436064221 its reverse (122460634531), we get a palindrome (257896698752).

The spelling of 135436064221 in words is "one hundred thirty-five billion, four hundred thirty-six million, sixty-four thousand, two hundred twenty-one".