133333209 has 15 divisors (see below), whose sum is σ = 199332133. Its totient is φ = 88819524.

The previous prime is 133333199. The next prime is 133333223. The reversal of 133333209 is 902333331.

The square root of 133333209 is 11547.

It is a perfect power (a square), and thus also a powerful number.

133333209 is a `hidden beast` number, since 1 + 3 + 333 + 320 + 9 = 666.

It is a de Polignac number, because none of the positive numbers 2^k-133333209 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (133333229) by changing a digit.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 103282 + ... + 104564.

Almost surely, 2^133333209 is an apocalyptic number.

133333209 is the 11547-th square number.

133333209 is the 5774-th centered octagonal number.

It is an amenable number.

133333209 is a deficient number, since it is larger than the sum of its proper divisors (65998924).

133333209 is an frugal number, since it uses more digits than its factorization.

133333209 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2578 (or 1286 counting only the distinct ones).

The product of its (nonzero) digits is 4374, while the sum is 27.

The cubic root of 133333209 is about 510.8727961326.

The spelling of 133333209 in words is "one hundred thirty-three million, three hundred thirty-three thousand, two hundred nine".