133531613 has 4 divisors (see below), whose sum is σ = 134779680. Its totient is φ = 132283548.

The previous prime is 133531609. The next prime is 133531621. The reversal of 133531613 is 316135331.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 316135331 = 3539 ⋅89329.

It is a cyclic number.

It is not a de Polignac number, because 133531613 - 2² = 133531609 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 (133531633) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 623873 + ... + 624086.

It is an arithmetic number, because the mean of its divisors is an integer number (33694920).

Almost surely, 2^133531613 is an apocalyptic number.

It is an amenable number.

133531613 is a deficient number, since it is larger than the sum of its proper divisors (1248067).

133531613 is a wasteful number, since it uses less digits than its factorization.

133531613 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1248066.

The product of its digits is 2430, while the sum is 26.

The square root of 133531613 is about 11555.5879556170. The cubic root of 133531613 is about 511.1260688002.

Adding to 133531613 its reverse (316135331), we get a palindrome (449666944).

The spelling of 133531613 in words is "one hundred thirty-three million, five hundred thirty-one thousand, six hundred thirteen".