1329729640 has 96 divisors (see below), whose sum is σ = 3107889000. Its totient is φ = 511961600.

The previous prime is 1329729631. The next prime is 1329729673. The reversal of 1329729640 is 469279231.

It can be written as a sum of positive squares in 4 ways, for example, as 1138792516 + 190937124 = 33746^2 + 13818^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 8924286 + ... + 8924434.

Almost surely, 2^1329729640 is an apocalyptic number.

1329729640 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 1329729640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1553944500).

1329729640 is an abundant number, since it is smaller than the sum of its proper divisors (1778159360).

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

1329729640 is a wasteful number, since it uses less digits than its factorization.

1329729640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 355 (or 304 counting only the distinct ones).

The product of its (nonzero) digits is 163296, while the sum is 43.

The square root of 1329729640 is about 36465.4581761974. The cubic root of 1329729640 is about 1099.6499271693.

The spelling of 1329729640 in words is "one billion, three hundred twenty-nine million, seven hundred twenty-nine thousand, six hundred forty".