1328487840 has 72 divisors (see below), whose sum is σ = 4533469668. Its totient is φ = 354263040.

The previous prime is 1328487793. The next prime is 1328487841. The reversal of 1328487840 is 487848231.

It can be written as a sum of positive squares in 2 ways, for example, as 1220244624 + 108243216 = 34932^2 + 10404^2 .

It is a tau number, because it is divible by the number of its divisors (72).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (1328487841) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 459841 + ... + 462720.

Almost surely, 2^1328487840 is an apocalyptic number.

1328487840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1328487840 is an abundant number, since it is smaller than the sum of its proper divisors (3204981828).

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

1328487840 is a wasteful number, since it uses less digits than its factorization.

1328487840 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 922582 (or 922571 counting only the distinct ones).

The product of its (nonzero) digits is 344064, while the sum is 45.

The square root of 1328487840 is about 36448.4271265579. The cubic root of 1328487840 is about 1099.3075090462.

It can be divided in two parts, 13284 and 87840, that added together give a square (101124 = 318²).

The spelling of 1328487840 in words is "one billion, three hundred twenty-eight million, four hundred eighty-seven thousand, eight hundred forty".