133136321 has 4 divisors (see below), whose sum is σ = 133301700. Its totient is φ = 132970944.

The previous prime is 133136317. The next prime is 133136357. The reversal of 133136321 is 123631331.

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 83631025 + 49505296 = 9145^2 + 7036^2 .

It is a cyclic number.

It is not a de Polignac number, because 133136321 - 2² = 133136317 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (133136621) 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, 81476 + ... + 83093.

It is an arithmetic number, because the mean of its divisors is an integer number (33325425).

Almost surely, 2^133136321 is an apocalyptic number.

It is an amenable number.

133136321 is a deficient number, since it is larger than the sum of its proper divisors (165379).

133136321 is an equidigital number, since it uses as much as digits as its factorization.

133136321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 165378.

The product of its digits is 972, while the sum is 23.

The square root of 133136321 is about 11538.4713458933. The cubic root of 133136321 is about 510.6212102140.

Adding to 133136321 its reverse (123631331), we get a palindrome (256767652).

The spelling of 133136321 in words is "one hundred thirty-three million, one hundred thirty-six thousand, three hundred twenty-one".