133645336213561 has 4 divisors (see below), whose sum is σ = 136166946330852. Its totient is φ = 131123726096272.

The previous prime is 133645336213553. The next prime is 133645336213573. The reversal of 133645336213561 is 165312633546331.

It is a happy number.

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 34591089453561 + 99054246760000 = 5881419^2 + 9952600^2 .

It is a cyclic number.

It is not a de Polignac number, because 133645336213561 - 2³ = 133645336213553 is a prime.

It is a super-2 number, since 2×133645336213561² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 133645336213499 and 133645336213508.

It is not an unprimeable number, because it can be changed into a prime (133645336213541) 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, 1260805058566 + ... + 1260805058671.

It is an arithmetic number, because the mean of its divisors is an integer number (34041736582713).

Almost surely, 2^{133645336213561} is an apocalyptic number.

It is an amenable number.

133645336213561 is a deficient number, since it is larger than the sum of its proper divisors (2521610117291).

133645336213561 is an equidigital number, since it uses as much as digits as its factorization.

133645336213561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2521610117290.

The product of its digits is 10497600, while the sum is 52.

Adding to 133645336213561 its reverse (165312633546331), we get a palindrome (298957969759892).

The spelling of 133645336213561 in words is "one hundred thirty-three trillion, six hundred forty-five billion, three hundred thirty-six million, two hundred thirteen thousand, five hundred sixty-one".