1329788640 has 48 divisors (see below), whose sum is σ = 4188835728. Its totient is φ = 354610176.

The previous prime is 1329788561. The next prime is 1329788651. The reversal of 1329788640 is 468879231.

It is a tau number, because it is divible by the number of its divisors (48).

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a self number, because there is not a number n which added to its sum of digits gives 1329788640.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1384717 + ... + 1385676.

It is an arithmetic number, because the mean of its divisors is an integer number (87267411).

Almost surely, 2^1329788640 is an apocalyptic number.

1329788640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1329788640 is an abundant number, since it is smaller than the sum of its proper divisors (2859047088).

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

1329788640 is a wasteful number, since it uses less digits than its factorization.

1329788640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2770411 (or 2770403 counting only the distinct ones).

The product of its (nonzero) digits is 580608, while the sum is 48.

The square root of 1329788640 is about 36466.2671519858. The cubic root of 1329788640 is about 1099.6661907225. Note that the first 3 decimals are identical.

The spelling of 1329788640 in words is "one billion, three hundred twenty-nine million, seven hundred eighty-eight thousand, six hundred forty".