133611613 has 4 divisors (see below), whose sum is σ = 138218940. Its totient is φ = 129004288.

The previous prime is 133611607. The next prime is 133611617. The reversal of 133611613 is 316116331.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 316116331 = 31 ⋅10197301.

It can be written as a sum of positive squares in 2 ways, for example, as 56821444 + 76790169 = 7538^2 + 8763^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-133611613 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 (133611617) 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, 2303620 + ... + 2303677.

It is an arithmetic number, because the mean of its divisors is an integer number (34554735).

Almost surely, 2^133611613 is an apocalyptic number.

It is an amenable number.

133611613 is a deficient number, since it is larger than the sum of its proper divisors (4607327).

133611613 is an equidigital number, since it uses as much as digits as its factorization.

133611613 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4607326.

The product of its digits is 972, while the sum is 25.

The square root of 133611613 is about 11559.0489660698. The cubic root of 133611613 is about 511.2281218432.

Adding to 133611613 its reverse (316116331), we get a palindrome (449727944).

The spelling of 133611613 in words is "one hundred thirty-three million, six hundred eleven thousand, six hundred thirteen".