133538440 has 64 divisors (see below), whose sum is σ = 347788800. Its totient is φ = 45197568.

The previous prime is 133538401. The next prime is 133538453. The reversal of 133538440 is 44835331.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19102 + ... + 25138.

It is an arithmetic number, because the mean of its divisors is an integer number (5434200).

Almost surely, 2^133538440 is an apocalyptic number.

133538440 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 133538440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (173894400).

133538440 is an abundant number, since it is smaller than the sum of its proper divisors (214250360).

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

133538440 is a wasteful number, since it uses less digits than its factorization.

133538440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6134 (or 6130 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 31.

The square root of 133538440 is about 11555.8833500516. The cubic root of 133538440 is about 511.1347793423.

The spelling of 133538440 in words is "one hundred thirty-three million, five hundred thirty-eight thousand, four hundred forty".