133531321 has 12 divisors (see below), whose sum is σ = 169454160. Its totient is φ = 104049960.

The previous prime is 133531319. The next prime is 133531339. The reversal of 133531321 is 123135331.

It is a happy number.

It is not a de Polignac number, because 133531321 - 2¹ = 133531319 is a prime.

It is a super-2 number, since 2×133531321² = 35661227376010082, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 133531292 and 133531301.

It is not an unprimeable number, because it can be changed into a prime (133531621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 123331 + ... + 124408.

It is an arithmetic number, because the mean of its divisors is an integer number (14121180).

Almost surely, 2^133531321 is an apocalyptic number.

133531321 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

133531321 is a deficient number, since it is larger than the sum of its proper divisors (35922839).

133531321 is a wasteful number, since it uses less digits than its factorization.

133531321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 247764 (or 247757 counting only the distinct ones).

The product of its digits is 810, while the sum is 22.

The square root of 133531321 is about 11555.5753210301. The cubic root of 133531321 is about 511.1256962319.

Adding to 133531321 its reverse (123135331), we get a palindrome (256666652).

The spelling of 133531321 in words is "one hundred thirty-three million, five hundred thirty-one thousand, three hundred twenty-one".