133609944 has 128 divisors (see below), whose sum is σ = 384975360. Its totient is φ = 38320128.

The previous prime is 133609909. The next prime is 133609951. The reversal of 133609944 is 449906331.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 308352 + ... + 308784.

It is an arithmetic number, because the mean of its divisors is an integer number (3007620).

Almost surely, 2^133609944 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 133609944, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (192487680).

133609944 is an abundant number, since it is smaller than the sum of its proper divisors (251365416).

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

133609944 is a wasteful number, since it uses less digits than its factorization.

133609944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 521 (or 517 counting only the distinct ones).

The product of its (nonzero) digits is 69984, while the sum is 39.

The square root of 133609944 is about 11558.9767713237. The cubic root of 133609944 is about 511.2259931777.

The spelling of 133609944 in words is "one hundred thirty-three million, six hundred nine thousand, nine hundred forty-four".