133604221 has 4 divisors (see below), whose sum is σ = 136446912. Its totient is φ = 130761532.

The previous prime is 133604209. The next prime is 133604239. The reversal of 133604221 is 122406331.

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: 122406331 = 149 ⋅821519.

It is a cyclic number.

It is not a de Polignac number, because 133604221 - 2¹⁵ = 133571453 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 133604192 and 133604201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133604201) 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, 1421275 + ... + 1421368.

It is an arithmetic number, because the mean of its divisors is an integer number (34111728).

Almost surely, 2^133604221 is an apocalyptic number.

It is an amenable number.

133604221 is a deficient number, since it is larger than the sum of its proper divisors (2842691).

133604221 is an equidigital number, since it uses as much as digits as its factorization.

133604221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2842690.

The product of its (nonzero) digits is 864, while the sum is 22.

The square root of 133604221 is about 11558.7292121582. The cubic root of 133604221 is about 511.2186938504.

The spelling of 133604221 in words is "one hundred thirty-three million, six hundred four thousand, two hundred twenty-one".