133228813 has 8 divisors (see below), whose sum is σ = 145930680. Its totient is φ = 121067520.

The previous prime is 133228783. The next prime is 133228829. The reversal of 133228813 is 318822331.

It can be written as a sum of positive squares in 4 ways, for example, as 31561924 + 101666889 = 5618^2 + 10083^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 133228813 - 2⁹ = 133228301 is a prime.

It is a super-2 number, since 2×133228813² = 35499833226777938, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133228013) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 134628 + ... + 135613.

It is an arithmetic number, because the mean of its divisors is an integer number (18241335).

Almost surely, 2^133228813 is an apocalyptic number.

It is an amenable number.

133228813 is a deficient number, since it is larger than the sum of its proper divisors (12701867).

133228813 is a wasteful number, since it uses less digits than its factorization.

133228813 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 270287.

The product of its digits is 6912, while the sum is 31.

The square root of 133228813 is about 11542.4786332919. The cubic root of 133228813 is about 510.7394285035.

The spelling of 133228813 in words is "one hundred thirty-three million, two hundred twenty-eight thousand, eight hundred thirteen".