1328816720 has 320 divisors, whose sum is σ = 4103737344. Its totient is φ = 387932160.

The previous prime is 1328816669. The next prime is 1328816771. The reversal of 1328816720 is 276188231.

It is an interprime number because it is at equal distance from previous prime (1328816669) and next prime (1328816771).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 11759384 + ... + 11759496.

Almost surely, 2^1328816720 is an apocalyptic number.

1328816720 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 1328816720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2051868672).

1328816720 is an abundant number, since it is smaller than the sum of its proper divisors (2774920624).

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

1328816720 is a wasteful number, since it uses less digits than its factorization.

1328816720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250 (or 244 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 38.

The square root of 1328816720 is about 36452.9384275123. The cubic root of 1328816720 is about 1099.3982162931.

The spelling of 1328816720 in words is "one billion, three hundred twenty-eight million, eight hundred sixteen thousand, seven hundred twenty".