133321328 has 160 divisors (see below), whose sum is σ = 335216640. Its totient is φ = 50077440.

The previous prime is 133321319. The next prime is 133321333. The reversal of 133321328 is 823123331.

It is a junction number, because it is equal to n+sod(n) for n = 133321297 and 133321306.

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, 2836601 + ... + 2836647.

It is an arithmetic number, because the mean of its divisors is an integer number (2095104).

Almost surely, 2^133321328 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 133321328, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (167608320).

133321328 is an abundant number, since it is smaller than the sum of its proper divisors (201895312).

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

133321328 is a wasteful number, since it uses less digits than its factorization.

133321328 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155 (or 149 counting only the distinct ones).

The product of its digits is 2592, while the sum is 26.

The square root of 133321328 is about 11546.4855259079. The cubic root of 133321328 is about 510.8576214685.

Adding to 133321328 its reverse (823123331), we get a palindrome (956444659).

It can be divided in two parts, 1333 and 21328, that multiplied together give a square (28430224 = 5332²).

The spelling of 133321328 in words is "one hundred thirty-three million, three hundred twenty-one thousand, three hundred twenty-eight".