133720320 has 144 divisors (see below), whose sum is σ = 432673920. Its totient is φ = 35192832.

The previous prime is 133720303. The next prime is 133720333. The reversal of 133720320 is 23027331.

It is a super-2 number, since 2×133720320² = 35762247961804800, which contains 22 as substring.

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, 372301 + ... + 372659.

It is an arithmetic number, because the mean of its divisors is an integer number (3004680).

Almost surely, 2^133720320 is an apocalyptic number.

133720320 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 133720320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (216336960).

133720320 is an abundant number, since it is smaller than the sum of its proper divisors (298953600).

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

133720320 is an equidigital number, since it uses as much as digits as its factorization.

133720320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 480 (or 466 counting only the distinct ones).

The product of its (nonzero) digits is 756, while the sum is 21.

The square root of 133720320 is about 11563.7502567290. The cubic root of 133720320 is about 511.3667300805.

Adding to 133720320 its reverse (23027331), we get a palindrome (156747651).

The spelling of 133720320 in words is "one hundred thirty-three million, seven hundred twenty thousand, three hundred twenty".