133205436 has 144 divisors (see below), whose sum is σ = 420848064. Its totient is φ = 34587648.

The previous prime is 133205431. The next prime is 133205453. The reversal of 133205436 is 634502331.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (133205431) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 238870 + ... + 239426.

It is an arithmetic number, because the mean of its divisors is an integer number (2922556).

Almost surely, 2^133205436 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 133205436, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (210424032).

133205436 is an abundant number, since it is smaller than the sum of its proper divisors (287642628).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

133205436 is a wasteful number, since it uses less digits than its factorization.

133205436 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 660 (or 655 counting only the distinct ones).

The product of its (nonzero) digits is 6480, while the sum is 27.

The square root of 133205436 is about 11541.4659380860. The cubic root of 133205436 is about 510.7095544502.

Adding to 133205436 its reverse (634502331), we get a palindrome (767707767).

The spelling of 133205436 in words is "one hundred thirty-three million, two hundred five thousand, four hundred thirty-six".