133205251 has 4 divisors (see below), whose sum is σ = 141040872. Its totient is φ = 125369632.

The previous prime is 133205243. The next prime is 133205287. The reversal of 133205251 is 152502331.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 133205251 - 2³ = 133205243 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (133205201) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3917785 + ... + 3917818.

It is an arithmetic number, because the mean of its divisors is an integer number (35260218).

Almost surely, 2^133205251 is an apocalyptic number.

133205251 is a deficient number, since it is larger than the sum of its proper divisors (7835621).

133205251 is an equidigital number, since it uses as much as digits as its factorization.

133205251 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7835620.

The product of its (nonzero) digits is 900, while the sum is 22.

The square root of 133205251 is about 11541.4579235034. The cubic root of 133205251 is about 510.7093180201.

Adding to 133205251 its reverse (152502331), we get a palindrome (285707582).

The spelling of 133205251 in words is "one hundred thirty-three million, two hundred five thousand, two hundred fifty-one".