1328538240 has 128 divisors (see below), whose sum is σ = 4705300800. Its totient is φ = 354272256.

The previous prime is 1328538229. The next prime is 1328538241. The reversal of 1328538240 is 428358231.

It is a tau number, because it is divible by the number of its divisors (128).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 1328538195 and 1328538204.

It is not an unprimeable number, because it can be changed into a prime (1328538241) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 21162 + ... + 55721.

Almost surely, 2^1328538240 is an apocalyptic number.

1328538240 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1328538240 is an abundant number, since it is smaller than the sum of its proper divisors (3376762560).

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

1328538240 is an equidigital number, since it uses as much as digits as its factorization.

1328538240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76911 (or 76893 counting only the distinct ones).

The product of its (nonzero) digits is 46080, while the sum is 36.

The square root of 1328538240 is about 36449.1185078597. The cubic root of 1328538240 is about 1099.3214106658.

Subtracting from 1328538240 its reverse (428358231), we obtain a square (900180009 = 30003²).

The spelling of 1328538240 in words is "one billion, three hundred twenty-eight million, five hundred thirty-eight thousand, two hundred forty".