209508133 has 4 divisors (see below), whose sum is σ = 209598220. Its totient is φ = 209418048.

The previous prime is 209508113. The next prime is 209508139. The reversal of 209508133 is 331805902.

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 149010849 + 60497284 = 12207^2 + 7778^2 .

It is a cyclic number.

It is not a de Polignac number, because 209508133 - 2²¹ = 207410981 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 209508095 and 209508104.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (209508139) 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, 41460 + ... + 46237.

It is an arithmetic number, because the mean of its divisors is an integer number (52399555).

Almost surely, 2^209508133 is an apocalyptic number.

It is an amenable number.

209508133 is a deficient number, since it is larger than the sum of its proper divisors (90087).

209508133 is an equidigital number, since it uses as much as digits as its factorization.

209508133 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 90086.

The product of its (nonzero) digits is 6480, while the sum is 31.

The square root of 209508133 is about 14474.3957732266. The cubic root of 209508133 is about 593.9277659709.

The spelling of 209508133 in words is "two hundred nine million, five hundred eight thousand, one hundred thirty-three".